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RURAL  ECONOMY, 


IN  ITS  RELATIONS  WITH 


CHEmStRY.  physics,  AM)  METEOROLOGY 


OB, 


CHEMISTRY  APPLIED  TO  AGRICULTURE. 


J.  B.  BOUSSINGAULT, 

USHBSK  OF  THK   INSTITUTE   OF  FRAltCK,  XTO.,   KTO. 

TRANSLATED,  WITH  AN  INTRODUCTION  AND  NOTES, 

BT 

GEORGE  LAW,  Agbiculturibt. 


NEW-YORK: 

ORANGE    JUDD    &    COMPANY 

245   BROADWAY. 


(,- 


i^ 


hr^ 


i      A 


THE 


AUTHOR'S    PREFACE. 


In  the  work  now  published,  I  present  the  results  of  the  inquiries 
in  which  I  have  been  engaged  for  many  years,  and  which  were  un- 
dertaken in  the  hope  of  throwing  light  upon  various  points  of  prac- 
tical agriculture.  My  first  idea  was,  to  confine  myself  to  the  mere 
re-impression  of  the  several  papers  which  I  had  communicated  from 
time  to  time  to  different  periodicals,  with  the  addition  of  a  quantity 
of  inedited  matter  which  I  had  by  me.  But  upon  more  mature  con- 
sideration, I  was  led  to  believe  that  I  should  be  doing  a  useful  thing 
did  I  fill  up  the  numerous  gaps  which  must  necessarily  occur  be- 
tween papers  published  isolatedly,  at  dates  more  or  less  remote  from 
one  another,  and  treating  of  the  most  dissimilar  subjects.  I  have 
thus  been  led,  in  addition  to  my  own  observations,  to  give  those  of 
numerous  writers  on  almost  every  branch  of  agricultural  science, 
being  only  careful  to  confine  myself  in  each  instance  to  the  most 
authentic  practical  conclusions ;  for  it  is  certain,  that  practical  data 
have  the  most  direct  interest  for  rural  economy,  both  in  itself  and 
in  its  bearings  upon  the  general  science  of  political  economy. 

I  have  a  further  reason  for  the  plan  which  I  have  adopted,  which 
[  am  the  less  disposed  to  pass  by  in  silence,  inasmuch  as  it  may 
plead  in  excuse  with  those  who  might  be  disposed  to  criticize  the 
tone,  perhaps  somewhat  too  didactic,  of  my  work. 

I  was  invited,  in  conjunction  with  several  other  professors  attached 
to  a  great  educational  institution,  to  give  a  course  embracing  my 
views  upon  the  science  of  agriculture.  I  consented  to  this,  and 
prepared  my  lectures  ^  but  motives,  to  which  I  was  entirely  a 
stranger,  having  prevented  the  project  from  being  carried  out,  1 
made  up  my  mind  to  publish,  not  the  lectures  such  as  I  should  have 


IV  AUTHOR  S    PREFACE. 

delivered  them,  but  the  documents  which  would  have  formed  the 
basis  of  my  teaching. 

The  first  part  of  this  work  treats  in  succession  of  the  physical 
and  chemical  phenomena  of  vegetation  ;  of  the  composition  of  vege- 
tables and  their  immediate  principles ;  of  fermentation ;  and  of  soils. 
The  second  comprises  a  summary  of  all  that  has  yet  been  done  on 
the  subject  of  manures,  organic  and  mineral ;  a  discussion  of  the 
subject  of  rotations ;  general  views  of  the  maintenance  and  economy 
of  live-stock ;  finally,  some  considerations  on  meteorology  and  cli- 
mate, and  on  the  relations  between  organized  beings  and  the  atmo- 
sphere. 

I  have  endeavored,  therefore,  to  give  a  summary  view  of  all  the 
questions  of  rural  economy  that  admit  of  scientific  treatment.  It 
may  be  found,  perhaps,  that  the  number  of  these  questions  is  still  ex- 
tremely small.  Nevertheless,  in  regarding  the  multitude  of  inquiries 
that  have  been  instituted  within  a  very  few  years  only,  in  viewing 
especially  the  ever-increasing  interest  attached  to  researches  bear- 
ing upon  practical  agriculture,  we  are  bound  to  anticipate  progress, 
and  to  hope  for  conclusions  important  as  regards  science,  profitable 
to  practice,  and  useful  to  humanity. 


EDITOR'S   INTRODUCTION 


The  following  work  is  submitted  to  the  agritnltural  public  in  the 
fullest  confidence  that  it  stands  in  need  of  no  recommendatory 
strictures  on  the  part  of  those  who  have  undertaken  to  present  it  in 
its  present  form  to  the  English  agriculturist.  In  the  person  of  its 
distinguished  author  the  man  of  science  is  happily  associated  with 
the  practical  farmer — the  accomplished  naturalist,  the  profound 
chemist  and  natural  philosopher.  The  friend  and  fellow-laborer  of 
Arago,  Biot,  Dumas,  and  all  the  leading  minds  of  his  age  and  coun- 
try— M.  Boussingault's  title  to  consideration  is  recognised  wher- 
ever letters  and  civilization  have  extended  their  influeuce. 

Surely  the  collected  and  carefully  recorded  experience  of  such  a 
man,  experience  by  which  the  conclusions  of  the  member  of  the  In- 
stitute have  been  tested  and  weighed  by  the  results  of  the  farmer 
of  Bechelbronn,  must  have  value  in  the  estimation  of  every  educated 
mind,  and  cannot  fail  to  be  especially  welcome  to  that  class  of 
readers  who  are  professionally  engaged  in  the  practical  application 
of  that  noble  science  which  his  labors  have  contributed  to  illustrate 
and  advance. 

When  the  following  pages  were  confided  to  the  editor,  it  was  the 
impression  both  of  the  publisher  and  himself,  that  in  the  course  of  the 
work  many  points  would  necessarily  arise  demanding  elucidation, 
others  calculated  to  provoke  controversy  or  challenge  investigation, 
and  others  again  which  could  be  rendered  available  or  instructive 
to  the  British  agriculturist  only  by  means  of  copious  explanation, 
showing  with  what  modification  and  under  what  circumstances  the 
views  advanced  might  be  applicable  to  the  art  as  exercised  in  the 
climate  and  soil  of  this  country.  But  the  minute  and  analytical 
perusal  indispensable  in  the  operation  of  investing  the  Author's 
thoughts  and  expressions  with  an  English  garb,  has  demonstrated 
the  fallacy  of  this  impression,  and  if  possible  has  augmented  the 
admiration  of  the  untiring  patience,  the  vast  experience,  and  the  as- 
tute, circumstantial,  and  elaborate  accuracy  of  the  accomplished 
Author,  in  whose  researches  the  reader  will  find  the  profoundest 
sagacity,  combined  with  a  childlike  simplicity  which  communicates 
to  his  work  a  charm  not  necessarily  inherent  in  the  subject. 

This  is  not  iD*<^nded  to  imply  an  unqualified  approval  of  the  illus- 
trious philosopher's  manner  of  dealing  with  his  own  facts  and  obser 

1 


2  INTRODUCTION. 

vations  ;  still  less  of  nis  style  of  writing,  which  is  often  wanJe  ing 
and  diffuse,  and  which,  in  order  to  render  it  presentable  to  the  Eng- 
lish reader,  has  required  much  compression  and  retrenchment.  Still, 
however,  instead  of  having,  as  was  expected,  to  pause  at  each  step 
of  the  Author's  progress,  and  dissert  upon  his  views  upon  this  or 
that  particular  branch  of  his  subject,  the  observations  of  the  com- 
mentator must  of  necessity  be  restricted  in  a  great  degree  to  an  in- 
dication of  such  parts  of  the  work  as  in  his  judgment  are  the  most 
valuable  and  instructive,  together  with  such  incidental  objections  aa 
appear  to  be  of  sufficient  importance  to  require  stating  at  length. 

The  chemical  portion  of  the  work  is  of  inestimable  value  and  con- 
ducted with  consummate  skill  and  knowledge  ;  and  with  a  minute- 
ness and  accuracy  perfectly  unexampled.  At  the  same  time  the 
results  of  the  writer's  researches,  as  well  as  the  means  and  process- 
es by  which  these  results  were  obtained,  are  displayed  with  such 
absolute  perspicuity  as  to  be  intelligible  and  instructive  to  every 
agricultural  inquirer,  however  superficial  his  previous  acquaintance 
may  be  with  the  details  of  chemical  science. 

Nothing  from  the  pen  of  tlie  Editor  could  throw  additional  light 
upon  the  Author's  brilliant  and  most  interesting  elucidation  of  vege- 
table physiology :  his  exposition  is  at  once  masterly  and  complete, 
and  contains  much  that  is  both  valuable  and  new.  And  even  when 
the  novelty  of  the  facts  which  he  adduces,  or  the  originality  of  the 
inferences  deduced  and  unfoldea  may  admit  of  question,  they  are 
still -deserving  of  the  most  respectful  attention  from  the  new  and 
striking  lights  in  which  he  places  them,  and  presents  them  to  the 
agricultural  reader,  and  the  clear  and  convincing  way  in  which  he 
demonstrates  their  inter-dependency  and  their  most  intimate  con- 
nection with  many  of  the  most  important  pecuniary  and  professional 
interests  of  the  cultivator.  Every  intelligent  farmer  will  find  his 
account  not  merely  in  a  repeated  perusal  of  this  portion  of  the  work, 
but  in  regarding  it  as  a  text-book  and  manual  to  be  kept  by  him  for 
permanent  reference  and  consultation. 

The  arrangement  of  the  subject,  naturally  and  judiciously  adopted 
by  the  writer,  presents  the  consideration  of  soils  as  the  first  topic 
for  the  observations  of  the  agricultural  commentator  ;  but  on  this 
head  the  distinguished  author  is  so  thoroughly  explanatory  and  judi- 
cious, that  nothing  is  left  for  the  Editor  but  to  approve,  to  acquiesce, 
and  to  recommend  him  with  admiring  confidence  to  the  patient  con- 
sideration and  study  of  the  intelligent  inquirer. 

At  page  237  the  subject  of  manures  is  taken  up,  and  discussed 
with  characteristic  minuteness  through  many  succeeding  pages. 

It  may  perhaps  be  objected,  that  the  various  theories  respecting 
the  origin,  nature,  efficacy,  and  relative  nature  of  the  difl^erent  ma- 
nures in  use,  as  well  as  the  various  modes  of  their  produttion,  con- 
coction, and  application,  which  M.  Boussingault  has  here  collated 
and  elucidated,  contain  nothing  new ;  that  they  have,  in  fact,  under 
one  form  or  other,  been  long  familiar  to  practical  men ;  but  without 
impugning  the  justness  of  this  opinion,  the  Editor  has  long  been 
eonvinced  that  the  subject  has  received,  generally,  far  less  care  and 


INTRODUCTION.  3 

attention  than  it  so  eminently  deserves ;  and,  in  short,  that  it  is 
much  neglected  by  many  who  are  accounted  not  merely  intelligent, 
but  scientific  agriculturists ;  and  while  admitting  that  much  valuable 
information  has  been  frequently  given  to  the  agricultural  world  by 
the  repeated  experiments  of  several  enterprising  individuals  both  in 
Scotland  and  England,  he  still  most  urgently  recommends  a  careful 
study  of  this  part  of  the  work,  which  will  probably  lead  the  reader 
to  the  conclusion  that  the  methods  and  practice  recommended  by  the 
Author  are,  upon  the  whole,  those  best  worthy  of  adoption.  In 
page  260  will  be  found  some  very  urgent  warnings  against  what 
he  (M.  Boussingault)  regards  as  the  prevalent  and  pernicious  cus- 
tom of  turning  dung-heaps  "  frequently."  If,  however,  by  the  term 
"  frequently,"  a  course  not  exceeding  three  complete  turnings  of  the 
heap  be  comprehended,  the  Editor  can  by  no  means  coincide  with 
this  opinion ;  a  long  experience  having  convinced  him  that  there 
are  many  circumstances  under  which  the  Author's  recommendations 
would  be  found  not  merely  over-cautious,  but  positively  injurious. 
For  drill  crops,  for  instance,  when  it  happens  that  the  farm-dung  is 
somewhat  rough,  which  must  generally  be  the  case  towards  the 
close  of  every  season,  when  the  animal  dejections  are  scanty  and 
the  great  bulk  of  the  already  ripened  manure  has  been  carried  out 
upon  the  land,  and  the  fresh  additions  have  not  had  the  advantage 
of  being  compounded  with  matter  already  concocted,  an  extra  turn- 
ing is  very  advantageous. 

Every  farmer  will,  of  course,  turn  his  heap  once,  for  the  purpose 
of  thoroughly  mixing  the  various  ingredients  and  different  qualities 
of  manure  which  it  contains  ;  the  extra  turning,  even  admitting  that 
it  may  to  a  certain  extent  promote  the  over-decomposition  of  the 
manure,  and  dissipate  the  ammoniacal  principles  which  it  is  impor- 
tant to  preserve,  is  not  attended  with  so  great  a  loss  in  this  respect 
as  that  which  is  inevitable  from  keeping  open  the  drill  by  the  appli- 
cation of  coarse  dung,  which  cannot  fail  to  be  attended  with  a  most 
serious  loss  of  the  more  volatile  principles,  sometimes  even  laying 
the  manure  quite  bare,  and  in  the  case  of  turnips,  materially  ob- 
structing the  operation  of  sowing. 

Our  Author  brings  forward  the  authority  of  several  eminent  inqui- 
rers in  support  of  his  own  favorite  view  of  the  use  of  fresh  or  un- 
fermented  manure  ;  but  however  plausible  their  theories  may  appear, 
and  however  just  may  be  their  views  in  the  abstract,  there  are  many 
intermitting  circumstances  connected  with  the  general  economy  of 
a  farm,  which  must  govern  and  determine  their  adoption,  and  in 
which  the  practical  cultivator  must  be  guided  by  his  own  judgment 
alone. 

To  the  Author's  6th  chapter  the  reader  may  be  advantageously 
referred,  as  containing  a  very  full  and  valuable  description  and  dis- 
cussion, under  the  head  of  mineral  manures,  of  the  different  varieties 
of  the  class  usually  denominated  stimulants,  and  concluding  with  a 
brief  but  lucid  and  interesting  account  of  Water,  considered  as  an 
agent  of  vegetation,  and  of  its  importance  for  manuring  purposes. 

The  composition  and  preparation  of  liquid  manures,  as  well  asth« 


•  INTRODUCTION. 

various  means  of  procuring  and  preserving  them,  will  be  founc  to 
have  engaged  much  of  the  Author's  attention  ;  and  he  justly  points 
to  the  rapidity  of  their  ameliorating  action  as  a  peculiar  excellence, 
not  otherwise  attainable ;  at  the  same  time  admitting  that  in  the 
great  majority  of  cases,  the  great  and  unavoidable  expense  at- 
tending their  application,  however  moderate  may  be  the  prime-coit 
of  the  material,  has  always  operated  as  an  insuperable  obstacle  lo 
their  general  adoption.  In  the  justice  of  this  vital  objection,  most 
practical  agriculturists  who  have  used  them  to  any  extent,  will  read- 
ily concur ;  and  it  will  not  be  uninteresting  to  the  reader  to  learn 
that  there  is  reason  to  believe  that  it  will  henceforth  be  eflfectually 
obviated  by  the  use  of  a  very  simple  and  convenient  apparatus,  de- 
vised by  Mr.  Smith  of  Deanston,  a  zealous  and  able  friend  of  agri- 
culture, who  at  the  Highland  Society's  meeting  at  Glasgow  in 
autumn  last,  explained  the  details  of  his  contrivance  ;  and  the  Edi- 
tor has  reason  to  suppose  that  the  particulars  will  be  given  in  a  report 
of  the  proceedings  of  the  meeting,  in  the  forthcoming  January  publi- 
cation of  the  Highland  Society's  Transactions. 

The  Editor  is  anxious  to  direct  especial  attention  to  the  Author's 
7th  chapter,  wherein  he  treats  of  the  organic  and  inorganic  manures, 
and  of  crops — of  the  elements  of  manures  and  of  crops  with  their 
relations  inter  se^  &c. — a  section  of  the  work  which  presents,  in 
synopsis,  a  more  copious  and  complete  body  of  new,  interesting,  and 
important  facts,  of  a  nature  more  valuable  to  the  practical  farmer, 
than  has  ever  been  collected  in  any  previous  treatise  on  agricultural 
science.  The  great  mass  of  this  invaluable  information  is  condensed, 
as  it  were,  for  practical  reference,  and  displayed  in  copious  and 
elaborate  tabular  data— 3.  form  which,  though  not  attractive,  has 
enabled  the  writer  to  comprise  within  succinct  and  manageable  limits, 
a  quantity  of  instruction  which,  in  a  more  discursive  shape,  must 
have  distended  the  work  to  double  its  actual  size.  The  tables  ad- 
verted to,  present  not  merely  the  results  of  multifarious  experiments 
in  illustration  of  the  important  subject  of  rotation-cropping,  but  also 
these  results  as  especially  aflfected  by  the  application  of  the  various 
manures  to  which  the  several  experimenters  had  recourse.  The 
rotations  reported  may  appear  strange  and  curious,  and  sometimes, 
perhaps,  even  amusing  to  the  farmers  of  England  and  Scotland ; 
but  not  more  so,  in  all  probability,  than  those  which  are  A))1owed  in 
many  parts  of  our  Island  would  appear  to  the  cultivators  of  that 
part  of  Europe  where  our  Author's  agricultural  speculations  have 
been  carried  on,  and  where  the  bulk  of  his  analyses  have  been  ob- 
tained :  indeed,  locality  and  climate,  and  their  inseparable  concomi- 
tants, will  in  every  country  be  found  to  prescribe  and  control  the 
sorts  of  crops  which  may  be  rendered  the  most  subservient  to  the 
permanent  advantage  both  pecuniary  and  economical  of  the  hus- 
bandman. Thus,  with  regard  to  the  Author's  more  didactic  obser- 
vations and  positive  directions  on  the  subject  of  rotations,  there  is  no 
reason  to  doubt  that,  in  relation  to  the  soil,  climate,  and  geographical 
position  of  the  east  of  France,  where  his  experimental  course  of 
rotations  has  been  conducted,  they  are  highly  judicious,  and  hare 


INTRODUCTION.  5 

not  been  prescribed  and  required  without  mature  consideration. 
Moi'eover,  they  are  marked,  like  the  deductions  and  inferences  upon 
which  they  are  founded,  by  his  unusual  acumen,  patience,  and  saga- 
city ;  but  in  their  application  to  the  more  circumscribed  range  of 
culture  to  which  the  agriculturist  is  limited  in  the  ruder  and  more 
fickle  climates  of  north  and  of  south  Britain,  the  practice  of  the  cul- 
tivator must  be  governed  mainly  by  his  own  judgment  and  experi- 
ence in  the  circumstances  by  which  he  finds  himself  surrounded. 

The  interesting  and  ample  instruction  conveyed  in  the  observa- 
tions of  this  acute  and  profound  observer  upon  the  food  and  alimen- 
tary treatment  of  cattle  of  every  species,  accompanied  as  they  are 
by  minute  details  of  the  results  obtained  in  the  shape  of  organic  and 
inorganic  elements,  cannot  be  too  urgently  recommended  to  the  at- 
tentive consideration  of  every  one  interested  in  that  important  branch 
of  rural  economy  to  which  they  more  particularly  relate. 

The  Author's  strictures  comprehend  the  economy  of  the  domestic 
animals  with  the  exception  of  sheep,  a  subject  from  which  he  pro- 
fessedly abstains,  for  the  very  sufficient  reason,  that  in  his  opinion, 
his  opportunities  of  obtaining  accurate  information  thereupon  have 
not  been  sufficiently  ample  to  enable  him  to  discuss  it  with  confidence 
and  advantage.  His  theory  in  favor  of  the  superior  fattening  quali- 
ty of  hay  and  the  grasses  in  general  above  that  which  is  found  in 
tubers  and  roots,  (though  apparently  supported  by  his  usual  convin- 
cing appeal  to  experiment,)  will  be  received  with  considerable  al- 
lowance by  the  practical  farmer. 

We  have  many  instances,  in  the  present  day,  of  theories  ably, 
plausibly,  nay  even  satisfactorily  established,  which  are  nevertheless 
met  by  opposite  results  in  practice ;  and  the  hesitation  which  the 
Editor  ventures  to  intimate  upon  the  particular  point  in  question, 
will,  he  doubts  not,  be  readily  concurred  in  by  many  experienced 
feeders.  It  will  be  generally  admitted  that  the  boiled  or  steamed 
potato  possesses  a  much  higher  nutritive  value  than  belongs  to  it 
when  in  the  raw  state.  In  the  former  case,  however,  it  requires  to 
De  mixed  with  some  of  the  other  roots  which  are  not  characterized 
oy  the  same  property,  such  as  beet,  turnips,  &c. ;  the  Swede,  (Ruta- 
baga,) or  any  of  the  harder  sorts  are  best  adapted  for  this  purpose, 
and  form  a  complete  counteractive  to  the  dangerous  constipating 
tendency  of  the  boiled  potato  when  given  alone. 

There  are  many  different  substitutes  or  equivalents  in  the  shape 
of  mashes,  containing  leguminous  ingredients  which  are  admitted  to 
be  fully  as  nutritious  as  the  potato,  still  there  are  circumstances 
connected  with  market  value  which  render  it  a  most  valuable  re- 
source in  farm  alimentation.  The  popular  notion  that  (when  used 
ae  the  feed  of  horses)  the  boiled  or  steamed  potato  is  what  is  vul- 
garly called  "  soft  meat,"  tending  to  unfit  them  for  active  work,  is 
daily  losing  ground ;  for  not  only  is  it  rapidly  getting  into  more  gen- 
eral use  among  the  farmers  of  England  and  Scotland,  but  even  post- 
masters are  adopting  it  for  horses  employed  in  road  work. 

The  meteorological  section  of  the  volume  will  be  found  no  less 
instructive  to  the  agriculturist  than  fascinating  to  the  general  reader  ^ 

1* 


6  INTRODUCTION. 

no  eqaally  complete  and  extensive  body  of  new  and  interesting  fact* 
has  ever  before  been  presented  in  a  collected  form  to  the  agricultural 
world. 

It  will  be  observed  that  the  capital,  the  all-important  subject  of 
Draining,  as  the  great  master-engine  of  agricultural  improvement, 
is  merely  touched  upon  by  our  Author  in  a  cursory  way ;  shojld 
this  incite  a  feeling  of  disappointment,  it  must  be  borne  in  mind  that 
he  has  accomplished  all,  and  more  than  all,  that  he  nroposed  to  him- 
self, which  was  not  to  write  a  complete  work  on  practical  tillage, 
but  rather,  as  his  title  implies,  on  "  Rural  Economy,"  i.  e.,  the  eco- 
nomic production  and  application  of  the  produce  of  the  soil  under 
the  guidance  of  chemistry. 

Among  the  faults  of  execution  for  which  the  Translator  ventures 
to  solicit  the  agricultural  reader's  indulgence,  is  the  occasional  adop- 
tion of  terms  which  are  rather  French  than  English.  Many  of 
these  words  are,  in  the  original,  not  merely  technical,  but  local  and 
provincial,  and  are  not  inserted  in  any  of  the  dictionaries.  More- 
over, in  the  description  of  certain  processes  and  operations,  the 
Author  has  occasionally  employed  terms  for  which  there  is  no  Eng- 
lish equivalent ;  and  the  Translator  had  frequently  no  other  choice 
than  that  of  either  leaving  the  sense  of  the  passage  obscure  and 
defective,  or,  on  the  other  hand,  of  adopting  the  barbarisms  in  ques- 
tion, which  not  only  deform  the  English  of  the  construction,  but 
cannot  fail  to  be  offensive  to  the  taste  and  professional  preposses- 
sions of  the  agricultural  reader. 

With  reference  to  the  weights  and  measures  made  use  of  in  the 
oiiginal,  it  may  be  proper  to  state,  that  (against  strong  temptation 
to  let  them  stand  as  in  the  French,  merely  adding  a  table  of  equiva- 
lents) they  have,  at  the  instance  of  the  Publisher,  been  reduced  into 
their  corresponding  quantities  in  the  English  standard.  Grammes., 
in  the  more  delicate  experiments,  have  been  reduced  into  grains 
troy,  assuming  the  gramme  as  equal  to  15.438  grains ;  in  less  deli- 
cate experiments,  grammes  have  been  converted  into  pennyweights 
(dwts.)  and  ounces  troy.  Kitogrammes  are  given  in  lbs.  avoir- 
dupois ;  and  where  the  quantity  was  large,  they  are  often  brought 
into  tons,  cwts.,  qrs.,  &c.,  taking  the  French  kilogramme  at  2.2 
lbs.  avoirdupois.  The  Litre^  or  present  French  measure  of  liquids, 
has  been  reduced  into  pints,  calculating  the  French  measure  at  1.76 
pints  English  imperial  measure.  The  Hectolitre  employed  in  mea- 
suring grain,  is  rendered  into  bushels,  estimating  it  at  22  gallons 
English  dry  measure.  The  old  French  Quintal  is  also  sometimes 
employed  :  this  measure  of  weight  has  been  either  reduced  to  its 
proper  corresponding  quantity,  1  cwt.  3  qrs.  24  lbs.  English,  or 
where  odd  numbers  might  be  disregarded,  it  has  been  called  2  cwts. 
The  Are.,  or  French  superficial  measure  of  quantity,  has  been  cal- 
culated throughout  at  120  square  yards  English :  the  Hectare  at 
2.4  acres  English. 

The  labor  of  reducing  these  measures  into  their  English  equiva- 
lents has  been  immense ;  and  errors,  in  spite  of  the  best  care  which 
could  be  exerted,  have  doubtless  in  various  instances  crept  into  tha 


INTRODUCTlOrf.  7 

reductions.  Slight  discrepancies  between  aggregate  sums  and  their 
component  quantities  will  also  be  apparent  here  and  there,  an  inex- 
actness which  arises  from  the  number  of  decimal  places  not  having 
always  been  carried  out  far  enough. 

Our  Author  often  quotes  English  agricultural  writers,  whose 
weights,  &c.,  he  has  always  been  at  the  pains  to  reduce  into  their 
corresponding  French  equivalents.  Not  having  at  all  times  the 
works  referred  to  at  command,  the  Editor  was  compelled  to  bring 
back  the  French  weight  or  measure  into  the  corresponding  English 
one  by  calculation.  Thus  from  not  knowing  the  precise  equiralents 
adopted  by  M.  Boussingault,  some  trivial  discrepancy  between  the 
computed  and  the  original  weights,  &c.,  may  have  resulted  ;  but  as 
the  quantities  that  have  been  treated  in  this  way  are  especially  im- 
portant as  relative,  scarcely  ever  as  absolute  quantities,  the  error 
where  it  occurs  can  be  of  no  real  consequence.  Metres,  centime- 
tres, and  millimetres  have  been  reduced  into  English  feet  and  inches, 
assuming  the  metre  as  equal  to  39.370  inches.  Finally,  and  to 
conclude  our  list  of  reductions,  (would  that  it  had  been  shorter !) 
the  degrees  of  the  centigmde  thermometer  have  been  brought  into 
degrees  of  the  only  scale  in  familiar  use  among  us,  viz.  Fahren- 
heit's. 

In  the  translation  the  Editor  has  endeavored  (not  always  with 
perfect  success)  to  be  as  little  technical  as  possible,  with  a  view  to 
the  convenience  of  the  general  reader.  In  a  very  few  places  he 
has  even  ventured  slightly  to  condense  the  style  of  the  original  in 
order  to  keep  the  volume  within  moderate  dimensions,  occasionally 
throwing  the  information  contained  in  a  table  into  the  text  or  nar- 
rative ;  and  where  the  Author  appeared  to  him  to  be  forgetting  the 
rural  economist  in  the  mere  chemist,  as  where  for  example  he  de- 
scribes the  special  modes  of  preparing  and  purifying  indigo,  &c.  he 
has  made  bold  to  retrench  details,  and  give  the  results  or  conclusions 
only.  All  analyses  bearing  on  the  practical  subject,  whether  it  was 
the  soil  that  produced,  the  crop  that  was  grown,  or  the  animal  which 
fed  on  that  crop,  have  been  scrupulously  retained.  In  conclusion, 
the  reader  is  earnestly  recommended  to  read  an  admirable  little 
work,  the  joint  production  of  Messrs.  Dumas  and  Boussingault,  en- 
titled in  the  original,  "  Essai  de  Statique  Chiraique  des  Etres  orga- 
nises," which  has  been  presented  in  a  clear  English  translation,  under 
the  title  of,  "  An  Essay  on  the  Chemical  and  Physiological  Balance 
of  Organic  Nature,"  and  may  be  regarded  as  a  most  valuable  intro- 
ductory aid  to  the  perfect  comprehension  of  Boussingault's  Philoso- 
phy of  Agriculture,  and  as  a  key  to  the  more  scientific  and  technical 
portions  of  the  work  now  submitted  to  the  public. 


CONTENTS 


CHAPTER  I. 


^2 


PHTMCAt  PHENOMENA  OF  VEGETATION.— VEGETABLE  PBTSIOLOOT 

^  n. — Chemical  phenomena  of  Tegetation 25 

Germination 26 

Germination  of  wheat 29 

Continued  germination  of  peas 30 

Continued  germination  of  wheat 31 

^  III.— Evolution  and  growth  of  plants 33 

Experiment  I.— Growth  of  Red  Clover  daring  three  months 44 

Experiment  II.— Growth  of  peas 45 

Experiment  III.— Growth  of  wheat 46 

Experiment  IV. — Growth  of  clover ••  47 

Experiment  v.— Vegetation  of  oats 48 

^  IV. — Of  the  inorganic  matters  contained  in  plants— their  origin — of  the  chemical 

nature  of  sap 52 

Quantity  of  ashes  contained  in  the  different  parts  of  vegetables,  according 

to  M.  de  Saussure 53 

Composition  of  the  substances  found  by  M.  de  Saussure 55 

Alkaline  salts  and  insoluble  substances  contained  in  ashes 56 

Alkaline  salts  and  insoluble  substances  of  ashes,  according  to  M.  Berthier.  •  57 

Composition  of  the  ashes  of  several  plants  analyzed  by  M.  Berthier 59 

Sap  of  the  Bambusa  Ouaduas 68 

Sap  of  the  banana  plant  (Musa  Paradisica) 68 

Milky  saps 69 

Sap  of  the  papaw-tree  (Carica  Papaya) 69 

Sap  of  the  cow-tree 69 

Milky  sap  of  the  Hura  Crepitans  (Ajuapar) 71 

Milky  sap  of  the  poppy  (Opium) 71 

Milk  of  the  Plumeria  Americana 72 

Sap  of  the  caoutchouc-tree 72 

Gummy  and  resinous  saps 73 

Saccharine  saps 74 

CHAPTER  n. 

Or  THE  CHEMICAL  CONSTITTTTION  OF  VEGETABLE  SUBSTANCES 75 

%  I. — Quarternary  azotized  principles  of  vegetables 76 

Composition  of  legumine  obtained  from  diffep^nt  seeds 78 

%  II. — Proximate  principles  with  a  ternary  composition :  of  starch 80 

Innline 87 

Of  woody  matter  and  cellular  tissue 87 

Density  of  different  kinds  of  wood,  according  to  Brisson 90 

Of  sugar 114 

Beet-root  sugar 121 

Palm  sugar 126 

Grape  sugar 126 

Saccharine  principles  not  fermentai)le 128 

Gum 129 

Vegetable  jelly :  pectine  and  pectic  acid 129 


10  CONTENTS. 

Put 

Of  vegetable  acids 131 

Of  the  vegetable  alkalies 131 

Of  fatty  substances 134 

Of  essential  oils • 141 

Of  resin 142 

Caoutchouc 143 

Vegetable  wax 143 

Chlorophylle 145 

Of  coloring  matters 145 

(  ilL — Composition  of  the  different  parts  of  plants 154 

Roots  and  tubers 154 

Barks 161 

Leaves 164 

Seeds 168 

Fleshy  or  pulpy  fruits 189 

CHAPTER  III. 

Or  THX   SACCHARINE    rRUITS,  JUICES,  AND  INrUSIONS  USED  IN  THE  PREPARATION 

or  FERKENTED  AND  SPIRITUODS  LIQUORS ••  •    193 

CHAPTER  IV. 

Or  SOILS 200 

Classification  of  soils 223 

CHAPTER  V. 

Or  MANURES 237 

Excretions  of  the  horse 267 

Excretions  of  the  cow 268 

Excretions  of  the  pig 268 

Animal  excrements 285 

Table  of  the  comparative  value  of  manures,  deduced  frjm  analyses  made 
by  Messrs.  Payen  and  Boussingault • 297 

CHAPTER  VI. 

Or  MINERAL  MANURES  OR  STIMULANTS •      303 

Calcareous  manures 303 

Of  alkaline  salts 316 

Growth  of  sainfoin  upon  soils  gypsed  and  ungypsed  in  1792, 1793,  and  1794.  321 

Comparative  growths  of  white  clover,  g>'psed  and  ungypsed,  by  Mr.  Smith.  322 
Experinjent  with  field-beet  or  mangel-wurzel,  opening  ine  rotation  with 

manured  soil,  1842 327 

Mineral  substances  contained  in  the  crop 32C 

Of  ammoniacal  salts 33i. 

Of  water 336 

CHAPTER  VII. 

Ur  THE  ROTATION  or  CROPS 341 

(  I.— Of  the  organic  matter  of  mauOre  and  of  crops 341 

Potatoes 348 

Wheat 349 

Wheat-straw 349 

Red  clover 349 

Turnips 350 

Oats 350 

Oat-straw 351 

Field -beet  or  mangel-wurzel 351 

Rye 351 

Rye-straw 351 

White  peas 358 

Feastraw -   •  35t 


CONTENTS.  II 

Page 

Jerasalem  potato  or  artichoke 3.52 

Dried  stems  of  Jerusalem  artichokes 352 

Table  of  the  proportions  of  water  contained  in  different  substances 353 

Composition  (»f  the  same  substances  dried  in  vacuo  at  230°  F 353 

Relation  of  manures  to  crops 354 

Desiccation  of  half-made  or  half-decayed  manure 354 

Experiment  I 354 

Experiment  II 354 

Experiment  HI 354 

Analyses  of  half-made  manures 354 

Composition  of  the  manures  analyzed 355 

Rotation  course,  No.  1 357 

Rotation  course,  No.  2 357 

Rotation  course,  No.  3 358 

Rotation  course,  No.  4 358 

Continuous  Jerusalem  potato  crop.  No.  5 358 

Quatrennial  rotation,  adopted  by  M.  Crud,  No.  6 358 

Summary 359 

J  ^l  -Of  the  residues  of  different  crops 360 

Potato  tops  or  hauni 361 

Leaves  of  field-beet  or  mangel-wurzel 361 

Composition  of  dry  leaves 361 

Wheat  stubble 362 

Clover  roots 362 

Composition  of  the  roots 362 

Oat  stubble 362 

Summary  of  the  foregoing  results 363 

§  111. — Of  the  inoi^anic  substances  of  manures  and  crops 364 

Composition  of  the  ashes  proceeding  from  the  plants  grown  at  Bechelbronn  366 
Mineral  substances  taken  up  from  the  soil  by  the  various  crops  grown  at 

Bechelbronn  upon  one  acre 366 

Table  of  the  mineral  matters  of  the  crops  and  manures  in  the  course  of  a 

rotation 369 

CHAPTER  VIII. 

Or  THE  VeKDINO   of  the    animals  BELONOING    to  ▲   FARM  ;  AND   OP  THE    IMME- 
DIATE PRINCIPLES  OF  ANIMAL  ORIGIN 375 

41. — Origin  of  animal  principles ., 375 

Of  the  food  of  animals  and  feeding 38(? 

Experiments  on  the  maintenance  of  horses 400 

Experiment  1 400 

Experiment  II. — Introduction  of  Jerusalem  potatoes  into  the  ration 401 

Experiment  III. — Ration  of  hay  and  potatoes 401 

Experiment  IV. — Substitution  of  oats  and  straw  for  a  portion  of  the  hay 402 

Experj,ment  V. — Potatoes  substituted  for  a  portion  of  the  hay 403 

Experiment  VI. — Jerusalem  potato  for  a  portion  of  the  hay 403 

Experiment  VII. — Introduction  of  field-beet  or  mangel-wurzel  into  the  ration  403 
Experiment  VIII. — Introduction  of  the  Swedish  turnip  into  the  ration  and 

replacing  a  portion  of  the  hay 404 

Experiment  IX.— Introduction  of  carrots  into  the  ration 405 

Experiment  X. — Boiled  rye  as  a  substitute  for  oats 405 

Table  of  the  nutritive  equivalents  of  difierent  kinds  of  forage 407 

^  n.— Of  the  inorganic  constituents  of  food 410 

^  m. — Of  the  fatty  constituents  of  forage ;  considerations  on  fattening 416 

CHAPTER  IX. 

Or  the  economy  of  the  animals  attached  to  a  FARM. — OF  STOCK  IN  GENERAL, 

AND  ITS  RELATIONS  WITH  THE  PRODUCTION  OF  MANURE 428 

$  I —Homed  cattle 430 

Table  of  milch-kine  three  years  of  age  and  upwards 440 


12  CONTENTS. 

$U.--Milch-kine .^48 

Experiment  I. — Two  hundred  days  after  calving 447 

Experiment  II.— Two  hundred  and  seven  days  after  calving 448 

Experiment  III. — Tw^o  hundred  and  fifteen  days  after  calving 448 

Experiment  IV. — Two  hundred  and  twenty-nine  days  after  calving 448 

Experiment  V. — Two  hundred  and  forty  days  after  calving 449 

Experiment  VI.  Two  hundred  and  seventy  days  after  calving 449 

Experiment  VII. — Two  hundred  and  ninety  days  after  calving 449 

Experiment  Vin 449 

Experiment  IX. — Thirty-five  days  after  calving 450 

Second  Series.    Experiment  I. — Begun  one  hundred  and  seventy-six  days 

after  the  calving 450 

Experiment  II. — One  hundred  aid  eighty-two  days  after  the  calving 450 

Experiment  III. — One  hundred  and  ninety-three  days  after  the  calving 450 

Experiment  IV. — Two  hundred  and  four  days  after  the  calving 451 

$  HI.— Fattening  of  cattle    452 

$  IV.— Of  horses 460 

$V.— Of  hogs 464 

$  VI. — Of  the  production  of  manure 471 

CHAPTER  X. 

Mbtcorolooical  considerations 475 

$  I.— Temperature 475 

$  II. — Decrease  of  temperature  in  the  superior  strata  of  the  atmosphere 478 

$  in. — Meteorological  circumstances  under  which  certain  plants  grow  in  different 

climates 481 

Cultivation  of  wheat,  Alsace *. 482 

Cultivation  of  wheat  in  America 483 

Intertropical  region 483 

Cultivation  of  barley 483 

Cultivation  of  maize  or  Indian  com 484 

Cultivation  of  the  potato 484 

Cultivation  of  the  indigo  plant ■....  485 

^  IV. — Cooling  through  the  night;  dew,  rain 486 

I  V. — On  the  influence  of  agricultural  labors  on  the  climate  of  a  country  in  lessen- 
ing streams,  &c < 495 


RURAL    ECONOMY, 


CHAPTER   I. 

PHYSICAL  PHENOMENA  OF  VEGETATION. VEGETABLE  PHYSIOLOGY. 

The  operations  of  agriculture  having-  for  their  object  the  produc- 
tion of  plants  which  are  either  essential  as  food,  or  useful  in  the  arts 
and  industrial  processes  of  man,  it  is  well  to  begin  with  a  summary 
view  of  the  principal  organs  of  which  vegetables  are  composed  ;  and 
by  the  instrumentality  of  which,  under  certain  influences  which  we 
shall  seek  to  appreciate,  all  the  phenomena  of  their  existence  are 
manifested. 

Plants  fixed  in  the  soil  by  their  roots,  live  in  the  atmosphere  by 
the  concurrence  of  their  green  parts  under  the  combined  actions  of 
light,  heat,  and  moisture.  We  shall  by  and  by  ascertain  at  the  cost 
of  what  elements,  and  under  what  conditions,  their  growth  and  com- 
plete development  are  accomplished. 

The  seed,  which  is  the  final  result  of  vegetable  life,  and  of  which 
the  aim  is  the  reproduction  and  multiplication  of  the  species,  should 
first  receive  our  attention.  The  seed  is,  if  we  may  so  speak,  the 
starting  point  of  all  husbandry ;  it  is  with  very  few  exceptions  the 
first  point  on  which  the  industry  of  the  farmer  exerts  itself. 

Nature,  to  ensure  the  preservation  of  seeds,  has  had  recourse  to 
infinite  care  and  foresight,  which  are  in  some  measure  an  assurance 
of  their  importance.  The  seed  is  often  placed  in  the  middle  of  an 
abundant  fleshy  pulp,  which  serves  to  afford  it  nourishment  or  ma- 
nure at  the  time  of  its  future  development.  Sometimes,  as  in  legu- 
minous plants,  it  is  lodged  between  thick  and  tough  membranes,  or 
is  covered  with  hard  but  flexible  scales,  as  in  the  gramineous  plants  ; 
or  again  it  is  enveloped  in  a  woody  substance  of  extreme  hardness, 
as  in  stone  fruits. 

Nature  does  not  show  herself  less  provident  in  furnishing  means 
for  scattering  seeds,  and  propagating  vegetable  species  at  great  dis- 
tances. There  are,  indeed,  seeds  which,  furnished  with  light  silky 
plumes  or  wings,  flutter  in  the  air,  and  are  transported  afar  by  the 
winds.  Others,  by  means  of  a  viscous,  hard,  impermeable  envelope, 
float  on  rivers,  and  descend  their  courses  without  suffering  the  slight- 
est change,  or  losing  their  germinating  power.  There  are  seeds 
again  of  a  sufficiently  coherent  texture  to  resist  the  digestive  action 

2 


14  ,       VEGETABLE    PHYSIOLOGY. 

of  the  Stomachs  of  animals  that  feed  on  the  fruits  which  contain 
them,  and  which  are  consequently  often  found  deposited  at  great 
distances  from  the  plant  which  produced  them  ;  they  are  thus  fre- 
quently dropped  to  germinate  and  flourish  at  the  tops  of  the  steepest 
mountains.  By  these  admirable  provisions  of  nature,  then,  the  air, 
the  water,  and  even  animals  themselves  become  the  vehicles  by 
which  the  migration  of  various  vegetable  species  over  the  surface 
of  the  globe  is  effected. 

We  distinguish  in  seeds  the  kernel,  and  the  integument  which 
covers  or  encloses  it.  In  the  kernel,  the  embryo  exists,  which,  as 
its  name  indicate^,  is  destined  to  reproduce  the  plant  of  which  the 
seed  is  the  issue.  The  embryo  is  formed  of  several  essential  parts  : 
—  1st.  of  the  radicle  ;  2d.  of  the  gemmule,  plumule,  or  rudiment  of 
the  stem,  which  by  its  extension  engenders  the  organs  that  are  to 
vegetate  above  the  ground  ;  3d.  of  cotyledons,  which  form  the  great- 
est portion  of  the  kernel,  aad  which  are  destined  to  support  the  plant 
during  the  first  periods  of  its  existence. 

In  most  cases,  the  cotylejjons  are  formed  of  two  lobes  which  sepa- 
rate during  the  act  of  germination.  The  plumule  presents  itself 
under  the  form  of  a  little  white  point  which  penetrates  into  the  in- 
terior of  botn  cotyledons.  The  radicle  is  of  a  slightly  conical  shape, 
and  is  first  seen  when  it  projects  externally  from  the  seed. 

The  seeds  of  gramineous  plants  do  not  separate  into  two  parts  at  the 
commencement  of  their  independent  existence.  They  are,  in  fact, 
seeds  which  have  but  a  single  cotyledon.  As  plants  which  spring  from 
seeds  of  one  or  of  more  cotyledons  present  capital  differences  in 
their  organization  at  large,  and  mode  of  development,  botanists  have 
established  two  grand  divisions  among  them — into  monocotyledonous 
vegetables,  and  dicotyledonous  or  polycotyledonous  vegetables. 

When  the  seed  is  gathered  in  its  state  of  perfect  maturity  it  is 
•completely  inert,  its  vital  functions  are  wholly  suspended,  and  it  may 
be  kept  often  for  a  very  long  time  without  being  made  to  grow. 

The  length  of  time  during  which  seeds  may  be  kept,  however, 
varies  extremely,  according  to  the  species.  There  are  plants,  for 
instance,  the  seeds  of  which  preserve  for  an  indefinite  period  'heir 
germinative  power ;  there  are  others,  on  the  contrary,  which  lose  it 
very  speedily. 

From  various  observations  which  appear  to  deserve  every  con 
fidence,  the  seeds — 

Of  Tobacco  have  germinated  after  having  been 

keptfor    10  yean. 

"Stramonium    25  "  (DuhameL) 

"  the  Sensitive  plant  60  " 

"Wheat    100  "  (Pliny.) 

"Wheat   10  "  (Duhimel.) 

"Melons  41  "  (Frievi^ald.) 

"Cucumbers   17  "  (Roger  Galen.) 

"Haricots  33  " 

"Idem.... 100  "  (Gerardin.) 

"Rape     17  "  (Leftbure.) 

"Rye 140  "  (Home.) 

The  seeds  of  the  coffee  plant  arc  perhaps  those  which  lose  the 


SEEDS.  .  15 

property  of  geiwiinating  most  speedily ;  planters  are  well  aware  that 
they  must  be  sown  almost  immediately  after  they  ate  taken  from 
the  bush.  Oleaginous  seeds  are  generally  preserved  with  great  dit-, 
ficulty  ;  so  also  are  those  of  rubiaceous  plants,  of  the-  laurels,  myr- 
tles, &c.*  ' 

In  practical  agriculture  there  is  always  much  advantage,  and 
additional  security,  in  sowing  the  most  recent  seed,  even  of  kinds 
wbitjh  are  known  to  be  the  longest  lived.  It  frequently  happens, 
even  after  a  very  short  time,  that  a  certain  proportion  of  these  seeds 
die  :  they  have,  perhaps,  not  been  gathered  under  circumstances 
favorable  to  their  complete  preservation.  It  is,  therefore,  only  when 
he  is  compelled  to  do  so,  that  the  farmer  trusts  wheat  to  the  ground 
which  has  been  gathered  in  former  years ;  and  experience  has 
proved  that  in  using  such  seed,  it  is  necessary  to  increase  very  con- 
siderably the  quantity  sown. 

The  inactivity  of  the  seed  ceases  so  soon  as  it  is  brought  into 
contact  with  water  and  the  air  under  the  influence  of  a  sufficient 
temperature.  Sown  in  moist  jsarth,  a  seedtabsorbs  water,  and  swells 
considerably  ;  the  pellicle  which  covers  it  becomes  distended,  and 
ends  by  bursting  ;  the  radicle  and  the  plumule  appear,  and  become 
more  and  more  distinct ;  the  root  penetrates  the  ground  ;  the  plu- 
mule by  and  by  grows  into  a  stalk  which  gets  greener  and  greener, 
increases  rapidly,  and  augments  the  number  of  its  leaves,  so  that 
the  young  plant  acquires  vigor  every  day.  At  a  certain  period, 
flowers  appear ;  and  these  are  succeeded  by  fruit,  the  final  term  of 
which  is  the  maturity  of  the  seed.  The  phenomena  of  vegetation 
then  cease.  The  whole  of  the  organs  of  annual  plants  now  wither 
and  die  ;  the  work  of  reproduction,  of  multiplication,  is  accomplished. 
Thus  begins  and  ends  the  existence  of  the  plants  which  are  the 
usual  subjects  of  our  husbandry. 

With  regard  to  biennial  plants  and  trees,  which  possess  more  than 
this  ephemeral  existence,  things  pass  differently.  The  plant  vege- 
tates so  long  as  the  temperature  of  the  atmosphere  and  moisture  of 
the  soil  are  favorable  to  it :  during  the  cold  season  the  leaves  fall, 
and  the  growth  is  suspended  ;  but  the  plant  revives  anew  on  the 
return  of  spring.  Those  vegetables,  the  stem  of  which  is  generally 
ligneous,  and  whose  roots  penetrate  deeply  into  the  ground,  have  a 
power  of  resisting  cold,  and  brave  the  rigors  of  the  winter.  In 
these  latitudes,  the  renewal  of  the  vegetation  of  trees  in  the  spring 
presents  an  obvious  analogy  to  the  process  of  germination  :  the  evo- 
lution of  the  buds  represents  this  process  very  closely  ;  and  the  phe- 
nomena at  large,  which  we  observe  in  annual  plants,  are  for  the 
major  part  reproduced  • — there  is  increase  of  size  in  the  stem  and 
root,  sprouting  of  leaves,  inflorescence,  ripening  of  fruits,  production 
of  seeds,  and  then  suspension  of  function. 

In  the  tropics,  where  the  temperature  is  nearly  uniform  through- 
out the  year,  vegetation  goes  on  without  interruption  ;  it  only  varies 
in  its  vigor,  and  this  is  determined  by  the  abundance  or  the  paucity 

♦  DecandoUe,  Physiology,  page  622 


18  VEGETABLE    PHYSIOLOGY. 

of  rains  and  dews.  The  leaves  which  have  conciirred  in  the  pro 
duction  of  the  fruit,  and  in  perfecting  the  seed,  fall  as  it  were  ex- 
hausted ;  but  they  are  soon  replaced,  and  their  fall  is  only  perceived 
by  their  presence  on  the  surface  of  the  ground. 

The  perfect  plant,  therefore,  whether  it  be  studied  among  annuals, 
or  among  trees  that  endure  for  a  century,  has  analogous  organs, 
destined  to  fulfil  the  same  functions,  to  conduce  to  the  same  end — 
the  reproduction  of  the  seed.  These  organs,  which  we  shall  study 
in  succession,  are,  1st.  The  roots ;  2d.  The  stem ;  3d.  The  leaves  ; 
4th.  The  appendages  of  the  fructification. 

When  we  follow  the  progress  of  a  seed  set  in  a  proper  soil,  we 
observe  that  from  their  very  first  appearance  the  roots  seek  or  tend 
towards  the  interior  of  the  earth ;  the  plumule,  or  young  stem,  on  the 
contrary,  takes  a  direction  diametrically  opposite ;  it  grows  verti- 
cally and  seeks  the  air. 

The  lateral  shoots  in  herbaceous  plants,  and  the  young  branches 
of  shrubs,  form  various  angles  with  the  principal  stem  or  trunk.  The 
first  tendency  of  the  branches  is  to  rise  vertically  ;  but  as  they  gain 
length  and  weight,  they  bend  more  or  less  downward,  yielding  to  the 
power  of  gravitation.  Mr.  Knight  showed,  by  a  series  of  ingenious 
experiments,  that  the  direction  taken  by  the  roots  and  branches  is 
mainly  due  to  this  force. 

This  able  observer  arranged  a  wheel  of  wood  in  such  a  way  that 
he  could  make  it  turn  with  different  velocities  in  planes  variously 
inclined  to  the  horizon.  The  wheel,  which  was  kept  in  motion  by 
a  stream  of  water,  could  be  made  to  revolve  vertically  or  horizon- 
tally at  will. 

A  number  of  beans  were  planted  upon  the  circumference  of  the 
wheel,  in  circumstances  known  to  be  indispensable  to  their  germi- 
nation and  growth.  By  giving  the  wheel  a  sufficient  -velocity,  it 
was  easy  to  make  the  centrifugal  force  greater  than  the  centripetal 
force.  In  Mr.  Knight's  apparatus,  this  happened  when  the  wheel 
in  the  vertical  plane  performed  one  hundred  and  fifty  revolutions  in 
a  minute.  The  whole  of  the  radicles  were  then  seen  to  turn  theii 
suckers  beyond  the  circumference  in  lines  which  were  prolonga- 
tions of  the  radii  of  the  wheel,  and  their  growth  took  place  in  planes 
perpendicular  to  its  axis. 

The  stems  took  a  completely  opposite  direction,  and  after  a  time 
their  summits  attained  the  centre  or  axis  of  the  wheel. 

In  causing  the  wheel  to  revolve  in  a  horizontal  plane,  the  same 
effects  were  still  observed,  when  the  rapidity  of  rotation  was  suffi- 
cient to  annul  the  action  of  terrestrial  gravitation.  But  when  the 
motion  was  so  far  diminished,  as  merely  to  modify  or  to  lessen  the  force 
of  attraction,  without  entirely  annulling  it,  the  plant  took  a  course 
comprised  in  a  plane  which  formed  a  certain  angle  with  the  circum- 
ference of  the  wheel.  With  a  certain  velocity,  the  roots  were  in- 
clined 10°  below  the  horizontal  plane  in  which  the  wheel  moved,  and 
the  stems  then  formed  an  angle  of  the  same  magnitude  above  the  same 
plane.  The  angle  of  deviation  formed  in  this  position  of  the  wheel  waa 
always  smaller  in  proportion  as  the  raj»idity  of  rotation  was  greater. 


STEMS.  17 

fow^  since  gravitation  influences  the  position  which  vegetables 
present,  as  these  beautiful  experiments  of  Mr.  Knight  demonstrate, 
a  practical  conclusion  which  seems  to  follow  from  the  fact  is  this, 
that  the  number  of  plants  which  may  be  placed  upon  a  certain  ex- 
tent of  soil,  does  not  depend  solely  on  the  extent  of  surface  ;  and 
that  the  power  of  production  of  a  field  which  is  very  much  sloped, 
does  not  exceed  its  horizontal  projection.  With  regard  to  creeping 
plants,  and  with  reference  to  meadows,  it  is  clear  that  this  principle 
is  not  rigorously  exact :  but  in  so  far  as  plants  with  isolated  stems 
are  concerned,  many  agricultural  philosophers,  and  among  the  num- 
ber Davy,*  have  admitted  it  as  perfectly  indisputable.  This  opinion, 
as  M.  Corrardf  has  judiciously  observed,  is  founded  on  the  geome- 
trical jrinciple,  which  in  itself  is  perfectly  true,  that  an  inclined 
plane  cannot  be  cut  by  a  greater  number  of  vertical  perpendiculars 
of  a  determinate  thickness,  than  the  horizontal  plane  which  serves  it 
for  a  base.  Thus,  says  Corrard,  as  buildings  which  rest  on  an  in- 
clined plane  are  raised  perpendicularly  to  the  horizon,  it  has  been 
concluded  that  an  inclined  plane  can  hold  no  larger  an  extent  of 
building  than  would  the  horizontal  plane  which  it  covers  ;  so  that 
inclinations  of  surface  do  not  actually  add  to  the  extent  of  towns.  It 
is  further  a  matter  of  absolute  certainty,  that  as  rain  falls  vertically, 
the  quantity  of  water  collected  upon  the  eaves  of  a  house  is  precisely 
the  same  as  that  which  would  be  gauged  in  the  same  place  upon  a 
horizontal  surface,  equal  to  that  of  the  building.  But  we  should 
very  much  deceive  ourselves,  adds  Corrard,  if  upon  the  same  prin- 
ciple we  inferred  that  on  the  surface  of  an  inclined  plane  we  could 
not  have  a  tree  more  than  upon  the  much  smaller  horizontal  plane 
which  serves  as  its  base. 

For  although  plants  grow  perpendicularly  to  the  horizon,  and  may 
in  this  respect  be  considered  as  so  many  vertical  perpendiculars  or 
laminae,  still,  from  circumstances  which  are  peculiar  to  them,  we 
cannot  here  apply  with  propriety  the  geometrical  principle  in  ques- 
tion. Because,  to  make  the  application  exact,  it  were  necessary  to 
suppose  that  plants  required  no  space  around  them  to  thrive,  and  that 
the  whole  surface  of  the  ground  might  be  covered  with  their  stems 
without  any  space  being  left  between  them,  and  without  this  prox- 
imity interfering  with  their  growth  and  vigor. 

But  such  a  supposition  is  impossible,  inasmuch  as  it  is  absolutely 
necessary  that  plants  should  have  a  certain  amount  of  space,  both  in 
the  ground  and  in  the  atmosphere,  in  which  to  extend  their  roots 
and  stretch  forth  their  branches.  Supposing,  therefore,  the  inclined 
plane  to  be  of  considerably  greater  extent  than  the  horizontal  plane 
which  supports  it,  it  will  necessarily  aflford  to  a  larger  number  of 
plants,  the  spaces  which  their  roots  require  for  their  growth  and 
nourishment.  In  other  words,  upon  the  inclined  surface  there  will 
be  a  larger  quantity  of  vegetable  earth,  and  more  of  the  nutritious 
iuices  favorable  to  vegetation ;  and  for  these  reasons  the  space  which 

♦  Agricultural  Chemistry,  vol.  i. 

t  B.  Corrard,  Verhandel.  von  der  Maatsch.  te  Haarlem,  vol.  xv.  p.  308. 

2* 


18  VEGETABLE    PHYSIOLOGY. 

must  always  exist  between  plants  may  be  less  than  on  the  horizontal 
plane.  Consequently,  all  the  conditions  necessary  to  fertility  being 
assumed  as  equal,  the  inclined  plane  will  be  capable  of  supporting 
a  larger  number  of  vegetables  having  vertical  stems  than  the  hori- 
zontal plane. 

The  organization  of  different  parts  of  plants,  so  worthy  in  all 
respects  of  exercising  the  sagacity  of  physiologists,  need  not  be 
made  a  subject  of  minu  ;e  research  in  this  place.  Generalities  suf- 
fice in  our  agricultural  science.  This  organization,  however  com- 
plex it  is  in  appearance,  is  probably  much  more  simple  than  is 
usually  believed  :  we  might  perchance  find  the  proof  of  this  sim- 
plicity in  the  readiness  with  which  organs,  the  most  dissimilar  in 
their  external  forms  and  so  different  in  their  functions,  undergo 
modification  and  transformation  one  into  another,  it  might  almost  be 
said  at  the  will  of  the  observer.  Thus  tubers,  those  fleshy  amyla- 
ceous bodies,  which  accumulate  on  the  subterranean  stems  of  cer- 
tain vegetables,  such  as  the  potato,  give  birth  to  a  plant  which  differs 
in  nothing  from  that  which  would  arise  from  the  seed  of  the  same 
vegetable.  Certain  leaves, — those  of  the  orange,  of  the  ficus  elas- 
tica,  &c.,  will  do  the  same.  Woody  stems,  branches  severed  from 
the  tree  and  planted  in  the  ground,  produce  roots  and  become  inde- 
pendent plants.  If  the  branches  of  certain  shrubs  be  buried,  and 
their  roots  be  exposed  to  the  air,  these  last  are  soon  seen  covered 
with  buds  and  leaves ;  while  the  buried  branches  acquire  a  fibrous 
capillary  structure,  and  in  no  great  length  of  time  they  both  present 
the  appearance  and  exercise  the  functions  of  roots.  This  singular 
mutation  readily  succeeds  with  the  willow,  and  it  was  upon  this  plant 
that  the  English  vegetable  physiologist,  Woodward,  effected  it  for 
the  first  time.* 

The  intimate  structure  of  the  roots,  trunk,  and  branches,  present 
considerable  similarity.  Divided  perpendicularly  to  their  longitudinal 
axis,  three  different  zones,  so  dissimilar  that  it  is  impossible  to  con- 
found them,  are  discovered  in  the  different  concentric  layers  which 
make  up  their  mass ;  these  are  the  bark,  the  wood,  and  the  pith. 
A  more  careful  examination  shows  that  each  of  these  zones  may  be 
further  subdivided. 

The  exterior  of  the  bark  is  covered  by  an  extremely  thin,  nearly 
transparent  and  porous  pellicle,  formed  by  an  assemblage  of  little 
adherent  scales ;  this  is  the  cuticle,  or  epidermis,  which  encloses  the 
entire  vegetable.  As  it  is  extensible  within  certain  narrow  limits 
only,  it  gives  way  and  cracks  in  proportion  as  the  body  of  the  tree 
increases  in  size.  The  pores  of  the  epidermis  are  minute  openings 
or  mouths  which  communicate  with  the  exterior  by  an  oval  orifice, 
surrounded  by  a  kind  of  contractile  margin.  It  has  been  remarked 
ihat  moisture  tends  to  close  these  pores,  and  that  drought  and  the 
action  of  solar  light  tend  on  the  contrary  to  make  them  open.  The 
chemical  nature  of  the  cuticle  which  covers  the  bark  appears  to  in- 
dicate that  it  is  destined  to  defend  the  plant  agaiast  the  too  direct 

*  DaTy'f  AKricoltoral  Chemiitry 


BARK.  1^ 

action  of  external  influences.  In  certain  trees,  the  cuticle  is  covered 
with  wax  or  resin.  The  most  remarkable  example  of  this  kind 
which  can  be  quoted,  is  that  of  the  wax-tree  (ceroxilon  andicola) 
which  grows  abundantly  upon  the  slopes  of  the  Andes.  This  tree, 
(a  palm,)  which  attains  a  height  of  between  130  and  164  English 
feet,  is  covered  over  the  whole  surface  of  its  trunk  with  a  mixture 
of  wax  and  resin.*  In  gramineous  plants,  the  epidermis  is  almost 
entirely  formed  of  silica.  The  bark  of  the  birch-tree  is  covered 
with  a  pellicle  of  an  unctuous  nature,  capable  under  the  agency  of 
nitric  acid  of  yielding  a  peculiar  suberic  (the)  acid.f 

After  the  epidermis,  in  going  from  the  circumference  towards  the 
centre,  a  layer  of  cellular  tissue  appears,  which  is  designated  by 
many  physiologists  under  the  name  of  the  herbaceous  envelope.  In 
the  cork  oak,  the  cork  represents  the  tissue  by  which  the  liber  or 
true  bark  is  covered,  an  organ  formed  of  a  vascular  tissue,  which 
with  care  can  be  separated  into  numerous  very  thin  flakes  or  layers, 
which  have  been  aptly  compared  to  the  leaves  of  a  book. 

The  origin  of  the  liber,  or  bark,  is  found  in  the  most  central  part 
of  the  trunk  ;  it  is  the  result  of  the  exudation  of  the  woody  parts,  as 
Duhamel,  with  the  same  wonderful  sagacity  which  characterizes  all 
his  works,  has  proved.  Having  cut  away  a  portion  of  the  bark  of 
a  tree  in  full  vigor,  and  taken  care  to  preserve  the  incision  from 
contact  with  the  air,  he  perceived  that  from  the  surface  of  the  wood 
laid  bare,  and  the  edges  of  the  bark  adhering  to  it,  a  viscous  mat- 
ter exudes,  which  accumulates,  acquires  consistency,  and  ends  by 
becoming  cellular,  thus  regenerating  the  liber  which  had  been  taken 
away.  Grew  called  this  viscous  secretion  cambium,  a  title  which  it 
still  retains.  It  is  now  generally  admitted  that  cambium  proceeds 
from  the  descending  sap. 

The  liber  is  a  very  important  organ  in  vegetables ;  we  know 
for  instance  that  it  is  necessary  for  the  success  of  a  graft  that  its 
liber  penetrate  or  be  penetrated  by  that  of  the  tree  on  which  it  is 
grafted. 

The  woody  layers  are  situated  under  the  liber.  Those  which  are 
at  the  greatest  distance  from  the  axis  of  the  trunk,  although  they 
present  the  fibrous  structure,  and  the  principal  characteristics  of  the 
woody  tissue,  still  differ  from  it  in  being  less  hard  and  less  tena- 
cious ;  this  zone,  which  at  the  first  glance  is  easily  distinguished 
from  the  wood  properly  so  called,  is  the  alburnum,  the  soft  or  false 
wood.  Its  fibres  are  much  looser,  and  its  color  paler  than  that  of 
the  wood  beneath  it,  the  difference  of  shade  being  particularly  ap- 
parent in  the  dye  and  deeply  colored  woods. 

The  alburnum  becomes  harder  and  tougher  with  age,  and  passes 
into  the  woody  tissue,  the  duramen  or  hard  wood,  properly  so  called. 
The  wood  begins  where  the  alburnum  terminates,  and  reaches  to 
the  centre,  to  the  pith  or  medullary  canal. 

In  dicotyledonous  trees,  a  certain  quantity  of  wood  is  formed 


•_ Boussingault,  sur  le  Palmier  a  cire.    Annales  ^  Climie  et  de  FhysiquA  3*  iitie^ 
the  observations  of  M.  Chevreul. 


t  59,  p.  19. 

t  ftOBt 


80  VEGETABLE    PHYSIOLOGY. 

during  vegetation  at  the  expense  of  the  alburnum ;  while  on  the 
opposite  side  towards  the  bark,  the  alburnum  increases  in  about  an 
equal  proportion  :  so  that  in  our  climates,  the  alburnum  grows  each 
year  from  a  new  concentric  layer  ;  but  in  tropical  countries,  where 
the  dicotyledonous  trees  vegetate  without  interruption,  the  annual 
concentric  layers  are  scarcely  perceptible.  To  prove  the  conver- 
sion of  alburnum  into  woody  tissue,  Duhamel  inserted  a  metallic 
wire  into  it  in  several  places.  At  the  end  of  a  few  years  he  found 
that  the  wire  had  become  engaged  in  the  proper  woody  layers. 

The  most  central  zone  of  the  trunk  or  stem  is  traversed  by  the 
medullary  canal  or  sheath,  which  is  usually  filled  with  the  pith,  a 
diaphanous  spongy  matter,  consisting  almost  entirely  of  cellular 
tissue. 

The  pith  sends  ramifications  towards  the  external  parts  of  the 
trunk.  Its  use  is  not  exactly  determined  ;  and  notwithstanding  the 
high  purposes  ascribed  to  it  by  some  physiologists,  we  have  many 
reasons  for  believing  that  its  functions  are  not  of  great  importance. 
Experiment  proves,  in  fact,  that  the  pith  may  be  removed  from 
young  trees  without  killing  them,  without  even  stopping  their 
growth.  One  of  the  least  unquestionable  offices  assigned  to  the 
pith,  is  that  of  its  being  a  reservoir  for  moisture  with  which  it  sup- 
plies the  plant  in  times  of  drought,  and  when  the  ground  does  not 
furnish  a  sufficient  quantity  of  water. 

The  internal  structure  and  progressive  development  of  the  stem 
of  monocotyledonous  plants  differ  essentially  from  those  which 
we  have  just  been  describing  in  connection  with  dicotyledonous 
plants. 

If  a  perpendicular  transverse  section  of  the  trunk  of  a  palm-tree 
be  examined,  the  same  arrangement  of  zones  which  is  observed  in 
the  dicotyledonous  plants  of  our  climates  will  not  be  perceived. 
The  regions  of  the  outer  bark,  of  the  liber  or  true  bark,  of  the  al- 
burnum, and  of  the  wood,  forming  so  many  concentric  circles  round 
a  canal  which  is  their  common  centre,  are  no  longer  distinguishable. 
The  trunk  of  the  palm-tree  presents  a  more  homogeneous  appearance. 
The  pith  is  disposed  through  the  whole  substance  of  the  stem,  and 
the  woody  tissue,  presenting  a  fibrous  texture  disposed  longitudinal- 
ly, is  found  intimately  mixed,  or  felted,  as  it  were,  with  the  medul- 
lary substance.  The  bark,  if  there  be  any,  is  always  very  indis- 
tinct ;  sometimes  reduced  to  a  simple  epidermis,  it  is  with  difficulty 
distinguished  from  other  parts  of  the  trunk.  In  the  beginning,  and 
when  it  first  appears  above  the  ground,  a  palm-tree  puts  forth  a  sys- 
tem of  leaves,  the  adhering  extremities  of  which  are  attached  in  the 
same  plane,  and  usually  surround  the  neck  of  the  root.  At  the 
second  shoot,  a  system  similar  to  the  preceding  one  appears,  which 
throws  off  the  outside  leaves,  and  interrupts  their  power  of  vege- 
tating. These  leaves  wither,  bend  towards  the  earth  and  fall  off, 
leaving  a  projecting  circular  ring  on  the  stem,  the  only  vestige  of 
their  existence.  The  same  phenomenon  takes  place  periodically. 
In  the  centre  of  the  crown  of  leaves  or  branches,  which  terminates 
tlie  palm-tree  plant,  a  bud  appears  which  is  at  first  small  and  blanciv 


FALMS.  9X 

ed  ;*  but  soon  displays  the  most  vigorous  powers  of  vegetation.  Its 
growth,  inflorescence,  and  progress  towards  maturity  are  indicated 
by  the  decay  and  fall  of  the  leaves  which  had  hitherto  protected  it. 
The  age  of  a  palnn-tree,  or  rather  the  number  of  times  that  it  has 
fructified,  or  become  crowned  with  fresh  leaves,  is  calculated  by  the 
number  of  woody  circles  which  are  found  marked  on  the  stem.  Its 
power  of  lasting  seems  to  have  no  other  limits  than  the  resistance 
which  the  base  offers  to  the  weight  it  supports.  In  these  colossal 
trees,  a  sensible  diminution  in  the  diameter  of  the  stem  is  often  per- 
ceptible towards  the  top,  and  in  most  of  the  species  ^t  's  a  fact 
equally  well  proved,  that  the  fruit  decreases  in  quantity  when  they 
have  attained  a  certain  epoch  of  their  existence.  In  the  cocoa-nut 
tree  {lodicen.  cncus  nucifera)  the  period  of  this  decrease  sh'jws  itself 
at  about  the  age  of  thirty  years,  although  this  tree  continues  to  bear 
for  nearly  a  century. f 

The  leaves,  the  forms  of  which  are  so  various,  present  however 
the  greatest  analogy  in  their  organization  :  the  green  membranous 
substance  of  which  they  are  almost  entirely  composed,  is  an  exten- 
sion of  the  parenchyma  ;  the  envelope  which  covers  them  answers 
to  the  epidermis. 

It  is  in  the  leaves  that  the  sap  is  subjected  to  the  action  of  the 
atmosphere  ;  it  is  there  concentrated  and  peculiarly  modified.  Ac- 
cording to  the  position  of  leaves  upon  the  plant,  their  under  sides, 
or  those  turned  towards  the  ground,  are  distinguished  from  their 
upper  sides  which  meet  the  light  from  above. 

The  upper  side  of  the  leaf  is  covered  with  a  thick  and  frequently 
shining  epidermis;  this  epidermis  is  sometimes  endued  with  a  sub- 
stance rich  in  silicious  matter,  as  in  rushes.  In  the  Steppes  of 
South  America  I  observed  a  tree,  called  Chapparal,  the  leaves  of 
which  are  S(»  highly  silicious,  that  they  are  used  for  polishing  metals. 
Generally  speaking,  the  covering  of  the  upfier  surface  of  leaves  is  a 
matter  which  is  something  of  the  nature  of  wax  or  resin.  The 
epidermis  which  covers  the  lower  surface  is  formed  in  most  cases 
r>f  a  very  thin,  rough  membrane,  full  of  cavities  and  frequently  cov- 
ered with  hairs  or  down. 

The  appearance  and  position  of  the  leaves  are  not  the  same  du- 
ring the  day  and  night.  In  the  dark,  simple  leaves  incline  to  fold 
up;  in  compound  leaves,  as  in  those  of  the  acacia  and  sensitive 
plant,  the  same  thing  is  still  more  marked  ;  the  effect  can  even  be 
produced  at  will.  If  during  the  day  a  sensitive  plant  is  placed  in  a 
dark  room,  the  leaves  immediately  close  ;  on  lighting  the  room  even 
with  candles,  they  open  again  as  if  under  the  influence  of  the  solar 
light  ;|  Linnaeus,  who  first  paid  attention  to  this  class  of  phenome- 
na, admits  that  plants  in  the  absence  of  light  experience  a  sort  of 
sleep. 

*  This  bvid,  in  certain  species  of  palm-trees,  is  sought  after  as  food,  and  is  often 
spoken  of  as  the  cabbage  of  the  pHJni-tree. 

t  Information  communicated  by  Mr.  Codazzi.  The  trunic  of  certain  species  of  palm- 
trees  shows  an  enlargement  towards  the  middle  of  its  height,  as  in  the  podma  Hrrigout 
vfChoco. 

X  Observation  of  M.  de  CandoUe. 


22  VEGETABLE    PHYSIOLOGY. 

The  fiower  is  the  forerunner  of  the  fruit,  the  fruit  is  the  medium 
in  the  heart  of  which  the  seed  is  developed.  The  organs  which 
constitute  the  flower  are  the  calyx  and  the  corolla,  destined  to  sup- 
port, nourish,  and  protect  the  pistil  and  the  stamina,  which  are  the 
essential  parts  ;  the  calyx  is  a  green  membrane  which  surrounds  the 
corolla,  and  in  certain  flowers  replaces  it. 

1  he  corolla  is  monopetalous  or  poly  petalous  according  as  it  is  com- 
posed of  one  or  of  several  pieces.  The  stamens  occupy  the  interioi 
of  the  corolla ;  they  aie  terminated  by  summits  of  a  vascular  tex- 
ture ;  these  are  the  anthers  ;  the  powder  which  covers  and  sticks 
slightly  to  them  is  designated  under  the  name  of  pollen. 

The  pistil  placed  in  the  middle  of  the  flower  is  composed  of  the 
ovary,  the  style,  and  the  stigma. 

Tiie  ovary  encloses  the  germ,  the  embryo  of  the  seed  ;  but  this 
embryo  is  only  developed  by  the  action  of  the  pollen.  The  style  is 
in  some  sort  the  tubular  prolongation  of  the  ovary  ;  it  supports  the 
stigma,  which  is  the  glandular  part  that  receives  the  fecundating 
influence  of  the  pollen. 

From  what  has  now  been  said,  the  pistil  may  be  considered  as  the 
female  organ  of  the  flower,  the  stamens  as  the  male  organs. 

Many  flowers  combine  the  organs  of  the  two  sexes.  These  flow- 
ers are  hermaphrodites ;  those  which  only  contain  one  organ,  are 
called  unisexual.  Both  male  and  female  flowers  are  produced  to- 
gether on  certain  plants ;  in  others,  the  flowers  are  all  only  of  one 
sex,  male  or  female.  Polygamous  plants  are  those  which  show  a 
union  of  male  and  female  flowers,  or  which  have  hermaphrodite 
flowers  on  the  same  stem. 

In  some  flowers,  the  sexual  organs  at  the  period  of  fecundation 
acquire  the  property  of  motion,  so  as  to  facilitate  this  grand  act 
The  stamens,  for  example,  are  seen  in  certain  plants  to  approach 
the  stigma,  to  deposite  their  pollen  on  it,  and  then  to  withdraw.  It 
occasionally  happens  again  that  stamens,  which  are  at  first  naturally 
in  a  position  inclined  with  reference  to  the  pistil,  become  suddenly 
straightened  in  such  a  A-ay  as  to  cast  their  pollen  on  the  female  or- 
gan, after  which  they  resume  their  original  position.  In  certain 
flowers  a  very  consideiable  evolution  of  caloric  has  been  perceived 
on  the  approach  of  the  period  of  fecundation.  In  some  arums,  for 
example,  the  temperature  has  been  observed  to  rise  to  40°  and  even 
50°  cent.  (104°  to  122°  Fahr.)  It  is  probable  that  this  phenomenon 
is  quite  general,  and  that  it  only  varies  in  point  of  intensity. 

Fecundation  accomplished,  the  office  of  the  flower  is  at  an  end. 
It  collapses,  withers,  and  dies.  But  the  impregnated  ovary  enlarges 
by  degrees,  until  it  has  attained  maturity,  when  it  presents  two  dis- 
tinct parts,  which  by  their  union  con»pose  the  fruit :  these  parts  are 
the  pericarp,  and  the  seed — the  husk  or  shell  and  the  grain.  The 
pericarp  always  surrounds  the  seed  ;  but  it  sometimes  happens  that 
it  is  so  thin  and  delicate  that  it  blends  with  the  seed. 

The  germination  of  seeds,  the  evolution  of  new  plants,  is  only 
accomplished  under  certain  physical  conditions  which  demand  oair 
consideration. 


ROOTS,    SAP.  28 

We  have  already  said  incidentally,  that  in  order  that  a  seed  may 
germinate,  it  must  be  in  contact  with  moisture,  have  communication 
with  the  air,  and  be  under  the  influence  of  a  certain  temperature. 
The  same  conditions  continue  to  be  indispensable  after  the  seed  has 
sprung,  and  the  plant  has  been  organized  ;  and  in  addition  the  access 
of  light  is  now  imperative. 

Roots  seek  in  the  soil  the  moisture  which  is  requisite  to  vivify 
the  whole  vegetable.  These  organs  are  terminated  by  hair-like 
fibres  of  extreme  delicacy,  and  having  sprngioles  at  their  extremities  : 
it  is  by  these  spongioit-s  that  absorption  is  effected.  Tlie  following 
experiment  is  sufficient  to  prove  that  this  is  l[ie  case  :  let  such  a 
plant  as  a  turnip  be  p  Aced  with  ilie  hair-like  extremities  of  its  root 
plunged  in  water,  and  the  plant  will  continue  to  live,  although  almost 
the  whole  body  of  the  root  is  in  the  air ;  let  things  be  now  so  ar- 
ranged that  the  hair-like  filaments  of  the  root  are  not  in  the  water, 
but  that  the  bulb  or  body  of  the  plant  is  so  :  the  leaves  will  soon 
droop  and  wither. 

The  force  which  brings  into  play  the  suction  power  of  the  roots, 
resides  in  almost  every  part  of  the  plant :  thus  a  root  deprived  of 
its  spongioles,  a  stem,  a  branch,  and  a  leaf,  exert  this  suction  power 
when  plunged  in  water.  But  the  absorption  eflfected  in  this  way 
has  a  limit,  and  we  soon  discover  the  necessity  of  making  fresh 
sections  of  the  extremities,  which  have  no  power  of  renovation  like 
the  filaments  furnished  with  spongioles,  which  terminate  a  root. 

We  are  still  ignorant  of  the  cause  which  produces  the  ascent  of 
liquids  in  vegetables,  and  which  carries  them  to  the  remotest  leaves 
in  spite  as  it  were  of  the  laws  of  hydrostatics.  We  readily  conceive 
how  the  spongioles  of  the  roots,  surrounded  by  earth  abundantly 
charged  with  moisture,  should  imbibe  by  the  simple  effect  of  poro- 
sity. We  can  also  understand  how,  after  having  been  modified  by 
the  spongioles,  the  water  and  the  principles  contained  in  it  should 
be  transformed  into  sap  ;  but  the  porosity  of  the  extremities  of  the 
roots,  and  the  chemical  modification  effected  by  the  spongioles  upon 
the  fluid  imbibed,  give  no  kind  of  explanation  of  the  rapid  ascent  of 
the  sap.  The  force  which  occasions  this  rise  is  very  considerable, 
as  was  demonstrated  by  Dr.  Stephen  Hales  in  a  series  of  ingenious 
experiments  more  than  a  century  ago. 

Hales  adapted  a  tube  bent  at  a  right  angle  and  filled  with  water, 
to  the  extremity  of  the  root  of  a  pear-tree,  the  point  of  which  had 
been  cut  off;  the  extremity  of  the  tube  opposite  to  that  which  was 
connected  with  the  root  dipped  into  a  bath  -of  mercury.  In  a  few 
minutes  a  portion  of  the  water  contained  in  the  tube  was  absorbed, 
and  the  mercury  rose  above  the  surface  of  the  bath  to  the  extent  of 
eight  inches.  In  the  beginning  of  April,  Hales  cut  oflf  a  vine  stem 
at  the  distance  of  thirty-three  inches  from  the  ground.  The  stem 
had  no  lateral  branches,  and  its  cut  surface,  which  was  nearly  cir- 
cular, had  a  diameter  of  ^ths  of  an  inch.  To  this  section,  he  adapt- 
ed a  reversed  syphon  :  and  things  being  so  disposed,  he  poured  in  a 
quantity  of  mercury,  which  after  a  time,  and  from  the  effect  of  the 
pressure  exerted  by  the  sap  as  it  escaped,  rose  in  one  of  the  armi 


24  VEGETABLE    PHYSIOLOGY. 

of  the  syphon,  and  remained  stationary  at  the  height  of  thirty-eigUt 
inches  above  its  original  level.  This  column  of  mercury,  it  is 
obvious,  represents  a  pressure  very  much  greater  than  that  of  oar 
atmosphere. 

The  ascent  of  the  sap  in  trees  takes  place  by  the  woody  layers. 
It  is  easy  to  obtain  conviction  of  this  by  making  a  plant  absorb  a 
watery  solution  of  cochineal.  By  making  sections  in  the  stem  at 
different  heights,  we  can  readily  trace  the  colored  liquid  in  its  pro- 
gress;  it  is  undoubtedly  the  course  which  the  natural  sap  would 
nave  taken.  We  see  no  indication  of  the  coloring  matter  in  the  pith 
nor  in  the  bark,  the  woody  tissue  alone  is  colored,  sometimes  en- 
tirely, but  more  generally  in  its  younger  parts  only.  The  dyeing 
which  results  from  this  injection  of  the  wood  is  in  lines,  and  parallel 
with  the  axis  of  the  trunk,  like  the  woody  fibres  themselves  ;  but 
in  some  cases  the  sap  may  deviate  from  the  rectilinear  course. 
Hales  showed  this  by  the  following  experiment :  upon  a  tree  he 
made  four  notches,  one  above  the  other  ;  each  notch  occupied  one 
quarter  of  the  trunk  and  reached  to  its  centre.  In  this  way  the 
whole  of  the  woody  fibres  were  cut  through  at  different  heights,  so 
that  to  continue  its  ascent  the  sap  must  necessarily  experience  a 
series  of  lateral  deviation,  which  in  fact  took  place. 

The  ascending  sap  of  vegetables,  as  it  has  hitherto  been  procured 
for  examination,  is  an  extremely  watery  fluid,  holding  in  solution 
very  small  quantities  of  divers  saline  and  organic  substances. 
Having  attained  the  leaves,  the  sap  there  undergoes  modification, 
and  becomes  concentrated  by  losing  water.  It  at  the  same  time 
experiences,  through  the  agency  of  the  atmospheric  air,  under  the 
influence  of  light,  a  great  modification  in  its  constitution.  Thus 
elaborated,  the  sap  takes  a  descending  course  ;  following  the  liher^ 
it  retrogrades  towards  the  soil,  and  therefore  performs  a  kind  of  cir- 
culation in  its  passage  through  the  plant.  The  descending  course 
of  the  sap  is  demonstrated  by  throwing  a  ligature  round  the  trunk 
of  a  tree  ;  after  a  time  there  is  formed,  above  the  part  that  is  tied, 
an  enlargement  which  is  owing  to  the  accumulation  of  the  principles 
of  the  sap  ;  but  below  it  the  tree  experiences  no  increase.  The 
descending  course  of  the  elaborated  sap  is  no  effect  of  simple  gravi- 
ty ;  because,  if  the  ligature  be  thrown  around  a  pendent  branch,  the 
enlargement  still  forms  between  the  ligature  and  the  free  extremity 
of  the  branch.  The  descending  sap  passing  through  the  cortical 
layers  must  necessarily  contribute  to  their  formation ;  and  it  is 
almost  certain,  as  appears  from  the  capital  experiment  of  Duhamel, 
that  it  is  the  cambium  which  is  changed  into  liber,  and  so  concurs  in 
the  growth  of  trees.  The  concentration  of  the  ascending  sap,  which 
occurs  during  its  passage  through  the  leaves,  by  the  simple  effect 
of  evaporation,  is  the  phenomenon  which  is  spoken  of  under  the 
name  of  the  exhalation  of  plants  :  this  exhalation  of  plants,  it  is 
easily  understood,  is  favored  by  a  high  temperature,  dryness,  and 
motion  of  the  air.  In  favorable  circumstances,  the  water  escapes 
in  the  state  of  vapor.  Hales  compared  the  watery  exhalation  of 
Dlants  to  the  perspiration  of  animals,  and  made  many  experiments 


EXHALATION.  25 

to  ascertain  the  quantity  of  watery  vapor  which  they  usually  throw 
off. 

Hales  planted  a  sun-flower  in  an  air-tight  vessel,  the  top  of  which 
was  sealed  hermetically  by  a  leaden  cover.  This  cover  was  pierced 
by  two  holes  :  one  for  the  passage  of  the  stem  of  the  plant,  the  other 
for  the  introduction  of  the  water  necessary  to  its  growth.  For  a 
fortnight  the  apparatus  was  regularly  wei.'rhed,  and  our  ingenious 
experimenter  found  that  the  green  parts  of  the  sun-flower  threw  off 
on  an  average  about  twenty  ounces  of  water  in  twelve  hours  of  Ihc 
day.  The  evaporation  was  always  increased  during  dry  and  warm 
weather  ;  moist  air  lessened  it ;  during  the  night  season,  the  evapo- 
ration was  sometimes  no  more  than  three  ounces,  and  it  occasional- 
ly happened  that  it  was  nil. 

Vegetable  life  appears  to  be  intimately  connected  with  the  pheno- 
menon of  evaporation.  From  the  inquiries  which  I  have  myself 
undertaken  on  this  subject,  so  well  deserving  the  attention  of  obser- 
vers, it  would  appear  that  a  plant  grows  only  when  it  transpires,  and 
that  in  hindering  this  transpiration,  we  in  fact  arrest  vegetation. 

We  now  associate  with  the  phenomenon  of  exhalation  the  source 
or  accumulation  of  certain  substances  which  are  met  with  in  con- 
siderable quantity  in  the  organization  of  plants,  although  scarcely  a 
trace  of  them  can  be  detected  in  the  water  with  which  they  are  sup- 
plied. The  water  evaporating,  leaves  these  substances  behind  ;  and 
as  the  mass  of  liquid  imbibed  by  the  roots  and  exhaled  by  the  green 
parts  is  very  considerable,  it  is  easy  to  conceive  how  they  should 
finally  come  to  be  present  in  rather  large  quantity. 

A  portion  of  the  water  which  a  plant  in  full  v\gor  absorbs,  must 
necessarily  enter  into  its  constitution  ;  the  water  exhaled  by  the 
leaves,  therefore,  cannot  equal  the  whole  of  that  which  has  been 
absorbed  by  the  roots.  Sennebier  endeavored  to  ascertain  the  rela- 
tion which  exists  between  the  absorption  and  the  exhalation,  and  ho 
found  in  the  particular  case  which  he  observed,  that  about  ^  of  the 
water  absorbed  was  fixed,  and  became  a  constituent  part  of  the 
vegetable. 


§  II.— CHEMICAL  PHENOMENA  OF  VEGETATION. 

The  chemical  phenomena  of  vegetation  are  accomplished  by  the 
concurrence  of  the  elements  of  the  atmosphere,  of  water,  and  of 
certain  organic  substances  which  exist  as  constituents  of  the  soil. 

The  action  of  the  atmosphere  upon  plants  presents  two  phases 
perfectly  distinct  from  one  another;  germination,  and  vegeta'ion 
properly  so  called,  which  last  comprises  the  development,  the  grov/th| 
and  the  multiplication  of  species. 

3 


26  CHEMICAL    PHENOMENA    OF   VEGETATION. 


GERMINATION. 

We  have  ascertained  that  a  seed,  considered  with  reference  to  its 
organization,  consists,  1st.  of  an  embryo  which  includes  the  germs 
of  the  root  and  of  the  stem;  and  2d.  of  the  cotyledon,  or  cotyledons. 
Considered  with  reference  to  their  chemical  compositions,  seeds  ex- 
hibit a  certain  similarity  of  constitution.  They  contain  :  1st.  starch 
and  gum  ;  2d.  a  highly  azotized  matter  analogous  to  the  caseum  of 
milk  and  animal  albumen  ;  this  is  the  matter  which  is  commonly  and 
very  improperly  designated  under  the  name  of  gluten,  and  of  vegeta- 
ble albumen  ;  3d.  a  fatty  or  oily  matter,  rich  in  carbon  and  hydrogen. 
Seeds  contain  either  fixed  oils,  such  as  hemp-seed,  rape-seed,  &c., 
or  volatile  oils,  as  aniseed,  cmnmin-seed,  &c.  The  different  prin- 
ciples which  are  associated  in  the  seeds  vary  considerably  in  their 
relative  proportions  :  they  also  vary  slightly  in  their  nature.  One 
seed,  that  of  the  colewort,  for  example,  will  contain  more  than  forty 
per  cent,  of  its  weight  of  oily  matter,  while  another,  such  as  wheat, 
will  only  contain  a  few  hundredths.  Oats  may  contain  ten  or  twelve 
per  cent,  of  caseum  or  gluten ;  in  certain  varieties  of  wheat, 
analysis  indicates  a  much  larger  quantity.  The  proportions  of  starch, 
gum,  sugar,  or  mucilage  do  not  vary  less.  It  almost  always  hap- 
pens that  these  different  substances  are  found  associated  in  the  same 
seed  ;  sometimes  one  predominates  and  the  others  only  enter  in  very 
small  proportion. 

After  burning,  the  ashes  of  seeds  are  always  found  composed  of 
phosphates,  sulphates,  and  alkaline  and  earthy  chlorides.  These 
ashes  also  contain  silica,  and  certain  carbonates  produced  by  the 
destruction  of  salts  formed  by  organic  acids. 

If  some  seeds,  sufficiently  moistened,  are  placed  under  a  bell- 
glass  containing  atmospheric  air  confined  over  quicksilver,  all  the 
signs  of  germination  will  soon  be  perceived.  In  the  course  of  a  few 
days,  provided  the  temperature  has  been  sufficiently  high,  germina- 
tion will  have  made  a  certain  progress.  Supposing  that  the  tem- 
perature of  the  bell-glass  has  not  varied,  and  that  the  atmospheric 
pressure  remains  the  same,  we  generally  find  that  the  air,  in  which 
germination  has  been  proceeding,  has  not  changed  its  original  vol- 
ume ;  but  it  has  been  modified  in  its  composition  :  a  notable  quantity 
of  carbonic  acid  has  been  formed,  and  a  portion  of  oxygen  has  dis- 
appeared. The  volume  of  carbonic  acid  produced,  represents  for  the 
most  part  the  volume  of  oxygen  which  has  disappeared.  Now  we 
know  that  carbon  being  burnt  in  a  certain  volume  of  oxygen  gas, 
produces  sensibly  an  equal  volume  of  carbonic  acid  gas.  It  was  the 
knowledge  of  this  fact  that  induced  M.  de  Saussure  to  say,  that  in 
germination,  carbonic  acid  is  produced  by  the  combustion  of  a  por- 
tion of  the  carbon  which  enters  into  the  composition  of  the  seed. 

Germination  and  the  appearance  of  carbonic  acid,  (which  is  al- 
ways its  consequence,)  take  place  as  readily  in  pure  oxygen  gas,  as 
in  atmospheric  air;  but  if  placed  in  an  atmosphere  deprived  of  oxy- 
gen, seeds  cease  to  germinate.  Consequently,  germination  is  out  of 
the  question  in  azote,  in  hydrogen,  or  in  carbonic  acid,  however  fa- 


GERMINATION.  27 

vorable  they  may  be  in  reference  to  humidity  and  temperature. 
Some  formation  of  carbonic  acid  is  indeed  to  be  observed  under 
such  circumstances,  but  then  this  gas  is  the  result  of  the  decompo- 
sition and  putrid  fermentation  of  the  seed.  It  is  therefore  by  means 
of  the  oxygen  which  it  contains,  that  atmospheric  air  concurs  in  the 
germination  of  seeds. 

Rollo  was  the  first  who  ascertained  the  production  of  carbonic  acid, 
during  the  germination  of  seeds  in  an  atmosphere  of  oxygen  ;  but  it 
was  M.  Theodore  de  Saussure,  who  by  delicate  eudiometrical  ex- 
periments, demonstrated  the  phenomena  in  all  their  nicety,  by  prov- 
ing thai  the  oxygen  consumed  was  replaced  by  a  corresponding 
volume  of  carbonic  acid.* 

There  are  some  seeds,  for  instance,  peas,  and  the  seeds  of  aquatic 
plants,  which  have  the  property  of  germinating  under  water.  Some 
observers  have,  from  this  fact,  come  to  the  premature  conclusion  that 
atmospheric  air,  and  consequently  oxygen,  were  by  no  means  neces- 
sary to  germination.  Saussure  has  explained  this  anomaly  by  re- 
ferring to  the  constant  presence  of  air  in  a  state  of  solution  in  water. 
In  fact,  having  placed  some  seeds  of  the  polygonum  amphibium  under 
water,  deprived  of  its  air  by  long  boiling,  Saussure  proved  that  ger 
mination  could  not  take  place. f 

Under  like  circumstances,  the  quantity  of  carbonic  acid  generated 
in  a  given  time,  is  by  so  much  greater,  the  larger  the  quantity  of 
oxygen  in  the  atmosphere  which  immediately  surrounds  the  ger 
minating  seed.  Carbonic  acid  gas  is,  of  all  the  gases  which  have 
been  tried,  that  which  is  most  unfavorable  to  germination ;  and  one 
way  of  hastening  the  process  is  to  place  under  the  receivers  which 
cover  the  seed,  some  substance  capable  of  absorbing  it  as  fast  as  it  is 
formorl — quick-lime,  for  example.  By  this  arrangement  the  radic- 
ular increase  is  sensibly  accelerated, J 

The  quantity  of  oxygen  gas  necessary  to  germination,  is  not  the 
same  in  reference  to  all  seeds ;  lettuce,  the  french-bean,  and  the 
field-bean  require  about  yg^th  part  of  their  respective  weights ;  while 
J^th  less  is  sufficient  for  wheat,  barley,  purslane,  &c.  Saussure 
moreover  came  to  the  conclusion  that  the  carbonic  acid  generated 
by  these  diflferent  seeds  in  germinating  is  proportioned  to  their  mass, 
and  altogether  independent  of  their  number.^ 

Inasmuch  as  seeds  during  germination  yield  carbonic  acid  to  the 
atmosphere,  it  is  quite  obvious  that  they  must  lose  some  part  of  their 
original  weight.  And  this  they  do  in  fact ;  but  the  loss  experienced 
by  seeds  which  have  germinated  is  always  greater  than  that  which 
would  have  resulted  from  the  destruction  of  carbon  that  takes  place. 
Saussure  attributed  this  excess  of  loss  to  the  volatilization  of  a  por- 
tion of  the  water  which  entered  into  the  composition  of  the  seed.jj 
According  to  Saussure,  therefore,  the  phenomena  of  germination 
resolve  themselves  into  the  diminution  of  carbon  and  of  the  elements 
of  water.     It  is,  nevertheless,  doubtful  whether  the  chemical  actions 

*  Saussure,  Recherches  chimiques  sur  la  V6g6tation,  p.  10. 

t  Idem,  p.  3.  t  Mem,  p.  26.  $  Idem,  p.  13.  ^|  Idem,  p.  ao. 


28  CHEMICAL    PHENOMENA,    ETC. 

are  so  simple  as  this ;  we  know,  for  example,  that  M.  Becquerel 
considered  the  organic  acid  which  appears  during  germination  as 
acetic  acid,  whereas  it  is  much  more  likely  tiiat  it  should  be  the 
lactic  acid.  There  is  certainty  of  the  formation  of  an  acid  during 
germination  ;  to  prove  its  development  it  is  sufficient  to  make  a  fev/ 
moist  seeds  sprout  on  blue  litmus  paper,  which  speedily  acquires 
the  permanent  red  tint  indicating  the  presence  of  an  acid. 

The  volume  of  the  air  in  which  seeds  germinate  is  not  absolutely 
invariable.  On  examining,  with  renewed  attention,  the  action  of 
germinating  seeds  on  a  limited  volume  of  air,  M.  de  Saussure  as- 
certained that  certain  seeds  have  the  property  of  diminishing  the 
bulk  of  this  atmosphere,  while  others  perceptibly  augment  it.  It 
must  be  admitted,  therefore,  that  during  germination,  tlie  volume  of 
carbonic  acid  produced  is  now  greater,  now  less,  than  the  volume  of 
oxygen  gas  that  is  consumed.  The  nature  of  the  results  obtained 
appears,  however,  to  vary  in  regard  to  the  same  class  according  to 
the  stage  of  the  germination. 

Elementary  analysis  appeared  to  me  the  most  satisfactory  means 
of  investigating  the  subject  of  germination.  I  shall  here  recapitu- 
late a  few  attempts  that  have  been  made  in  this  direction,  less  how- 
ever with  a  view  to  the  final  settlement  of  the  question,  than  to  point 
out  the  general  method  of  procedure  to  those  who  would  enter  far- 
ther upon  this  interesting  portion  of  physiology.  The  experiments 
I  allude  to  were  made  upon  the  seed  of  trefoil  and  on  wheat. 

The  seed,  on  being  dried  at  a  heat  of  110°  cent.  (230°  Fahr.,)  lost 
0.120  of  water.  Duly  moistened,  it  was  placed  to  sprout  on  a  por- 
celain plate.  As  soon  as  the  radicle  had  attained  a  length  of  from 
^•gth  to  2\th  of  an  inch,  each  seed  was  placed  in  a  stove,  the  temera- 
ture  of  which  was  sufficiently  high  to  check  the  growth  immediately. 
The  complete  desiccation  was  then  terminated  over  an  oil  bath  at  a 
temperature  of  110°  cent.  (230°  Fahr.) 

The  seed  put  to  germinate  weighed  2.474  grammes,  (38.193  grains 
troy;)  perfectly  dry,  its  weight  would  have  been  2.405  grms.  (37.128 
grains  troy.)  When  germinated,  the  seed,  also  quite  dry,  weighed 
2.241  grms.  (34.596  grains  troy.) 

Analysis  gives  us  the  composition  of 

THK  SEED  BEFORE  OERMtNATION.        THE  SEED  AFTER  OERMINATIOH. 

Carbon 51.5  ."id.S 

Hydrogen 6.0  O.Ii 

Azote    7.2  8.0 

Oxygen .♦■  36.0  34.2 

100.0  100.0 

RESULTS    OF    EXPERI.MENT. 

(jrains  troy.                       Carbon.          Hydrogen.  Oxyycn.  Ai.-'.e. 

Seed  placed  to  gemiinrite  37.12S  containing   18.865           2.22.3  13.360  2.670 

Seed  alter  gerniinatio:i       34.5%            "           17.815            2.176  11.840  2.7f]3 

Difference •  —  2.-532  '■       —  1.050       —  .047        —  1.520        +  .093 

The  total  loss  then  during  germination  was  0164  grm.,  (2.531  grs.) 
while  the  loss  due  to  the  carbon,  only  amounts  to  0.068  grm.  (1.C49 


GERMINATION.  29' 

grs. :)  the  analysis  shows  besides  that  in  this  particular  rase,  the 
excess  of  the  loss  in  the  present  case  over  and  above  that  which  is 
ascribed  to  the  carbon,  is  not  altogether  due  to  the  elenaents  of  water, 
inasmuch  as  it  is  partly  ascribable  to  carbonic  oxide ;  for 

1.049  grs.  of  carbon, 
1.404   "    of  oxygen, 

Represent  2.453  "    of  oxide  of  carbon. 

Supposing  this  to  be  so,  and  the  first  period  of  the  germination  of 
the  trefoil  to  have  been  conducted  in  a  close  vessel,  the  volume  of 
atmospheric  air  would  have  been  increased  ;  because  1  volume  of 
carbonic  oxide-(-i  volume  of  oxygen— 1  volume  of  carbonic  acid  gas. 
It  is  consequently  evident  that  for  each  volume  of  carbonic  oxide 
produced  from  the  seed,  there  is  one  half  of  this  volume  added  to 
the  total  volume  of  the  atmosphere. 

It  will  not,  perhaps,  be  useless  to  advert  to  the  circumstance  that 
the  increase  of  volume,  which  in  the  experiment  I  have  just  related 
must  have  amounted  to  about  twenty-five  cubic  inches,  would  cer- 
tainly have  passed  undetected,  if  the  experiment  had  been  conducted 
in  a  close  vessel.  For  inasmuch  as  several  quarts  of  atmospheric 
air  must  have  been  used  to  place  38.193  grs.  of  seed  in  conditions 
favorable  for  germination,  it  may  readily  be  imagined  that  the  in- 
crease of  volume  must  have  been  too  small  a  fraction  of  the  total 
mass  of  air  to  be  appreciated  with  any  certainty. 

GERMINATION    OF    WHEAT. 

The  wheat  employed,  on  being  dried,  lost  0.652  grain  of  moisture. 
Thirty-one  grains  were  arranged  for  germination,  which  process 
was  suspended  immediately  after  the  appearance  of  the  radicles. 
The  young  stalks  were  hardly  visible.  The  germinated  grain  looked 
slightly  shrivelled  :  on  being  crushed,  after  having  been  dried,  it 
scarcely  differed  in  appearance  from  ordinary  wheat  reduced  to 
powder,  a  considerable  quantity  of  starch  being  still  recognisable. 

The  wheat,  before  germinating,  taken  as  dry,  and  free  from  ashes, 
weighed  2.439  grms.,  or  37.653  grs.  troy. 

The  seed  when  germinated  and  gathered,  under  the  same  condi- 
tion, weighed  2.365  grms.,  or  36.510  grs.  troy. 

Elementary  analysis  gives  for  the  composition  of — 

WHEAT  NOT  GERMINATED.  GERMINATED  WHEAT. 

Carlwn 46.6  47.0 

Hydrogen    5-8  5-9 

Azote 3.45  3.7 

Oxygen ..-44.15  43.4 

100.0  100.0 

RESULTS    OF    EXPERIMENT. 

Grains  troy.                     Carbon.  Hydrogen.      Oxyg'en.  Azote. 

Wheat  placed  to  genninate    37.653  containing  17-47  2-176        16-56  1-281 

Wheat  when  germinated        36.510         "          17.15  2.145        15.83  1.343^ 

Diflference  —1.143          "       —0.032  — 0031    —0-073  +0.063 

3* 


30  CHEMICAL   PHENOMENA,  ETC. 

0.324  of  a  grain  of  carbon  -fO.432  of  a  grain  of  oxygen  represent 
0.756  of  a  grain  of  carbonic  oxide  ;  0.030  of  a  grain  of  hydro^ajn 
would  require  0.247  of  a  grain  of  oxygen  to  form  water.  Now,  the 
oxygen  remaining,  abstraction  made  of  that  which  enters  into  the 
formation  of  the  carbonic  oxide  is  0.282  of  a  grain. 

In  the  first  period  of  its  germination,  therefore  wheat,  like  trefoil 
seed,  experiences  a  loss  which  may  in  great  part  be  referred  to 
elimination  of  the  carbonic  oxide.  The  chemical  composition  of 
these  two  kinds  of  seed  at  more  advanced  periods  of  their  germina- 
tion, no  longer  presents  relations  so  simple.  We  easily  discover 
that  carbon  continues  to  be  eliminated  ;  but  the  loss  no  longer  cor- 
responds with  that  which  the  oxygen  of  the  seed  ought  to  suffer,  in 
order  that  the  total  loss  should  be  represented  by  a  definite  compound 
of  carbon.  The  phenomenon,  in  fact,  becomes  extremely  complex ; 
and  we  can  even  perceive  that  it  must  be  so,  when  we  reflect  that 
in  proportion  as  the  green  parts  are  evolved,  a  new  chemical  action 
is  set  up  entirely  different  from  that  which  takes  place  in  the  earliest 
periods  of  the  germination  :  the  green  matter  of  vegetables  having, 
as  we  shall  find,  the  singular  faculty  of  decomposing  carbonic  acid 
gas,  and  assimilating  its  carbon  under  the  agency  of  light. 

This  action  of  the  green  matter  begins  to  be  manifested  long  be- 
fore the  first  phases  of  germination  have  entirely  ceased  ;  so  that 
during  a  certain  time  two  opposite  forces  are  at  work  simultaneously. 
One  of  these,  as  we  have  seen,  tends  to  discharge  carbon  from  the 
seed  ;  the  other  tends  to  accumulate  this  element  within  it.  So  long 
as  the  first  of  these  forces  predominates,  the  seed  loses  carbon  ;  but 
with  the  appearance  of  the  green  matter  the  young  plant  recovers 
a  portion  of  this  principle  ;  finally,  when  by  the  progress  of  the  vege- 
tation, the  second  force  surpasses  the  first  in  energy,  the  plant  grows, 
increases,  and  advances  to  maturity. 

The  presence  of  light  is  indispensable  to  the  manifestation  of  the 
chemical  force  by  which  the  green  parts  of  plants  appropriate  the 
gaseous  elements  of  the  atmosphere.  Germination,  on  the  contra- 
ry, may  take  place  in  absolute  darkness  ;  and  it  would  be  curious  to 
inquire  into  the  issues  of  vegetation  begiin  and  ended  under  such  cir- 
cumstances, in  which  the  organs  produced  by  the  seed  would  have 
no  power  to  fix  any  of  the  principles  of  the  atmosphere  to  repair  the 
loss  of  carbon  which  the  seed  suffers.  It  is  evident  that  this  loss  of 
carbon  must  have  a  limit,  which  is  probably  that  of  germination. 


CONTINUED    GERMINATION    OP  PEAS 

Ten  peas,  weighing  together  2.237  grms.  or  34.534  grs.  troy, 
taken  as  quite  dry,  were  put  to  germinate  in  a  dusky  room,  the  tem- 
perature of  which  was  maintained  between  12°  and  17°  cent.  (54* 
and  G3°  Fahr.)  The  experiment,  begun  the  5th  of  May,  was  ended 
on  the  1st  of  July. 

The  germinated  peas,  when  dried,  weighed  1.075  grm.  or  16.595 
I  IS.  troy. 


GERMINATION.  81 


Composition  of  the  peas  : 


BEFORE   GERMINATION.  AFTER   OERMTNATIOM- 

Carbon 46.5  44.0 

Hydrogen 6.1  6.0 

Azote  4.2  6.7 

Oxygen 40.1  36.9 

Ashes 3.1  6.4 

100.0  ^                 100.0 

SUMMARY  OF  THE  EXPERIMENT. 

Graing  troy.      Carbon.    Hvdro^en.     Oxy»en.        Azote.  Balti,  Earth* 

Peas  set  to  germinate...  34.534  cont'ng    16.055      "2.115       13.843       1.447       1.064 
Peas  which  had  germi- 
nated  16.595  _  " 7.292      1.003 6.128 1.111 1064__ 

Difference — 17.939~"       —8.763—1.112      —7.715    —0.336       0.000 

Peas,  during  their  germination,  pushed  to  this  extreme  term, 
therefore,  suffered  a  loss  of  about  52  per  cent.,  the  loss  being  refer- 
able to  each  of  their  constituent  elements,  which  are  summed  up  in 
carbon,  water,  and  ammonia. 

7.719  of  oxygen  taking     0.972  of  hydrogen  to  form  water ; 
0.339  of  azote  requiring-  0.077  of  hydrogen  to  form  ammonia  ; 

1.049  which  represents  as  nearly  as  possible  the  quantity  of 
hydrogen  eliminated. 

In  this  experiment,  therefore,  we  see  that  a  seed  weighing  3.453 
grs.  troy,  suffered  a  daily  loss  of  about  0.077  of  a  grain  troy  of 
carbon. 

CONTINUED  GERMINATION  OF  WHEAT. 

On  the  5th  of  May,  46  corns  or  grains  of  wheat,  supposed  to  be 
quite  dry,  and  weighing  1.665  grm.  or  25.704  grs.  troy,  were  set  to 
germinate  in  the  dark. 

On  the  25th  of  June,  the  germinated  wheat,  when  dried,  weighed 
0.713  grm.  or  11.007  grs.  troy. 

Composition  : 

BEFORE   GERMINATION.  AFTER  GERMINATION. 

Carbon 45.5  41.1 

Hydrogen  5.7  6.0 

Azote 3.4  8.0  supposed. 

Oxygen  43.1  39.5 

Ashes 2.3  5.4  calculated. 

mo  iooio 


^  SUMMARY    OF    THE    EXPERIMENT. 

Grains  troy.  Carbon.    Hydrogen.    Oxyg^en.  Azote.  Salti,  Earth*. 

.   Wheat  placed  to 

germinate 25.704  containing  11.704      1.466      11.086  0.879      0.588 

Wheat  germina- 
ted     11-007        "  4.523      0.343        4.373  0-879      0.588 

Difference —14-697        "        —7.181—0-803   -6-713  0.000      0-000 

Diyjing  the  germination,  continued  for  fifty-one  days,  consequently 
thin  wheat  lost  57  per  cent.,  and  the  loss  may  be  wholly  referred  to 


82  CHEMICAL   PHENOMENA,    ETC. 

the  elements  of  carbonic  acid  and  water,  i.  e.  to  carbon,  hydrogen, 
and  oxygen.* 

These  results  of  the  elementary  analysis  of  seeds  of  different 
kinds,  before  and  after  germination,  tend,  therefore,  to  show  that  the 
chemical  phenomena  which  take  place  in  the  earliest  periods  of  ger- 
mination, continue  to  go  on  even  after  the  organic  matter  of  the 
seed  has  been  changed  into  a  proper  vegetable,  imperfect,  undoubt- 
edly, but  still  possessing  the  essential  organs  of  plants, — roots,  a 
stem,  and  leaves.  Deprived  of  light,  the  blanched  vegetable  may  be 
said  to  vegetate  in  a  negative  manner,  expending,  exhaling  the  ele- 
mentary principles  contained  in  the  seed  whence  it  sprung. 

The  general  practice  of  sowing  seeds  at  some  depth  in  the  ground, 
led  to  the  belief,  for  a  long  time,  that  light  was  prejudicial  to  germi- 
nation. Sennebier  had  even  inferred  so  much  from  his  experiments, 
which  appeared  to  derive  confirmation  from  those  of  Ingenhousz, 
and  which  were  instituted  for  the  express  purpose  of  discovering  the 
comparative  influences  of  sun-light  and  darkness  on  the  germination 
and  growth  of  vegetables.!  But  M.  de  Saussure  showed  that  the 
prejudicial  influence  attributed  to  the  light  was  connected  with  the 
drying  of  the  seed,  in  consequence  of  its  exposure  to  a  higher  tem- 
perature. M.  de  Saussure  caused  seeds  to  germinate  at  the  same 
time  under  two  bell-glasses  of  equal  capacity.  One  of  these  shades 
was  opaque,  the  other  was  transparent,  and  so  placed  as  to  re- 
ceive the  diffused  light  of  day.  The  temperature  was  the  same  in 
either.  The  seeds  sprung  simultaneously  under  both  glasses. J 
Within  a  few  days,  the  vegetation  under  the  transparent  shade  was 
most  advanced;  which  is  exactly  what  we  should  have  expecteci 
from  all  that  has  already  been  said  of  the  functions  of  the  organized 
parts  subjected  to  the  action  of  light. 

We  are  indebted  to  M.  de  Humboldt  for  a  number  of  very  curious 
observations  on  the  property  which  chlorine  possesses  of  stimulating 
or  favoring  germination.  This  action  of  chlorine  is  so  decided,  that 
it  is  apparent  even  upon  old  seeds  which  will  not  germinate  when 
placed  under  ordinary  circumstances.  The  experiments  of  M.  de 
Humboldt  were  made,  in  the  first  instance,  on  the  common  cress, 
{lepidium  sativum.)  The  seeds  were  placed  in  two  test  tubes  of 
glass,  one  of  which  contained  a  weik  solution  of  chlorine,  the  other 
common  water.  The  tubes  were  placed  in  the  dark,  the  tempera- 
ture being  maintained  at  about  15°  cent.  (59°  Fahr.)  In  the  chlo 
rine  solution,  germination  took  place  in  six  or  seven  hours  ;  from 
thirty-six  to  thirty-eight  were  required  before  it  was  manifest  in  the 
seeds  in  the  water.  In  the  chlorine,  the  radicles  had  attained  the 
length  of  .0585  Eng.  inch,  after  the  lapse  of  fifteen  hours,  wlvile 
they  were  scarcely  visible  at  the  end  of  twenty  hours  in  the  seeds 
submerged  in  vvater.^ 

•  The  small  quantity  operated  on  prevented  any  estimates  being  made  of  the  azote 
lost.  Its  projwrtion  was  supposed  not  to  have  varied.  It  is  extr?nieiy  prolrjiile,  how 
ever,  that  there  was  some  slight  disengagement  of  azote,  as  in  the  preceding  experi 
menu 

t  Saussure,  Rech.  Chimiques,  p.  23.  J  De  Saussiue,  op.  clt  p.  28^ 

^  Humboldt,  Flora  fribergensis  subteoanea,  p.  126. 


EVOLUTION    AND    GROWTH.  33 

In  the  botanical  gardens  of  Berlin,  Potsdam,  and  Vienna,  this  pro- 
perty of  chlorine  lias  been  made  available  to  excellent  ends;  by  its 
means  many  old  seeds,  upon  which  a  great  variety  of  trials  had 
already  been  made  in  vain  to  make  them  sprout,  were  brought  to 
germinate.  At  Schoenbrunn,  for  instance,  they  had  never  succeeded 
in  raising  the  clusea  rosea  from  the  seed  ;  but  M.  de  Humboldt  suc- 
ceeded at  once,  by  forming  a  paste  of  peroxide  of  manganese,  with 
water  and  hydrochloric  acid,  in  which  he  set  the  seeds  of  the  clusea, 
and  then  placed  them  in  a  temperature  of  from  62°  to  75°  cent. 
(143°  to  167°  Fahr.)  It  seems  very  likely  that  this  discovery  of  M. 
de  Humboldt  may  yet  be  taken  advantage  of  in  our  every-day  hus- 
bandry. It  is  quite  certain  that  the  whole  of  the  seed  which  we 
commit  to  the  ground,  does  not  spring  up,  especially  when  we  are 
forced  to  have  recourse  to  seed  that  is  two  or  three  years  old  ;  the 
loss  is  then  frequently  very  considerable.  But  a  solution  of  chlo- 
rine, or  a  mixture  which  would  evolve  it,  could  not  cost  much,  its 
use  would  add  little  or  nothing  to  the  very  trifling  expense  which  is 
generally  incurred  in  pickling  the  wheat  that  is  employed  as  seed. 


§  III.— EVOLUTION  AND  GROWTH  OF  PLANTS. 

As  germination  advances,  we  see  those  organs  acquiring  shape 
and  size  which  had  appeared  at  first  in  the  rudimentary  state.  The 
roots  extend  in  length,  and  increase  in  number,  and  their  extremities 
become  covered  with  capillary  fibres.  The  stem  as  it  rises  puts 
forth  branches  in  all  directions,  which  become  covered  with  leaves. 
The  cotyledons  which  had  nourished  the  young  plant  during  the 
first  days  of  its  existence,  wither  and  fall.  Under  the  influence  of 
the  solar  light,  the  vegetation  progresses  amain,  and  the  organic 
matter,  which  finally  constitutes  the  plant  when  it  has  attained  matu- 
rity, weighs  vastly  more  than  the  same  matter  which  existed  pre- 
viously in  the  seed.  To  quote  a  single  instance  from  the  family  of 
annual  plants,  a  seed  of  field  beet  of  the  weight  of  ,06175  of  a  crrain, 
may  by  the  end  of  the  autumn  give  birth  to  a  root  which  with  its 
leaves  shall  weigh  162099grs.  or  upwards  of  281bs.* 

This  immense  and  rapid  assimilation  can  have  no  other  source 
than  the  soil,  the  air,  and  water.  Without,  at  this  time,  pausing  to 
consider  the  useful  influence  which  the  soil,  and  the  substances  it 
contains,  exert  upon  the  entire  development  of  vegetables,  we  shall 
here  assume  it  as  a  general  principle  that  water  and  the  air  of  the 
atmosphere  alone,  are  capable  of  furnishing  them  with  all  the  ele- 
ments which  enter  into  their  composition,  to  wit — carbon,  hydrogen, 
oxygen,  and  azote.  In  other  words,  a  seed  may  germinate,  vegetate, 
give  birth  to  a  plant  which  shall  attain  to  complete  maturity,  by  the 

*  Actual  weight  of  a  beet-root  grown  at  Bechelbronn  in  1841 


34  EVOLUTION    AND    GllOWTH. 

mere  concurrence  of  water  and  the  gases,  or  vapors  which  are  dlf 
fused  through  the  atmosphere.  This  fact  is  demonstrated  by  the 
following  experiment : — 

In  a  sufficient  quantity  of  properly  moistened  roughly  pounded 
brick-dust,  (which  had  been  heated  to  redness  in  order  to  destroy 
every  trace  of  organic  matter,)  a  few  peas  were  sown  on  the  9th 
of  May,  and  the  pot  was  transferred  to  a  green-house  in  order  to 
protect  the  plants  from  the  dust  and  impurities  which  always  fiy 
about  in  the  open  air. 

On  the  16th  of  July,  the  peas,  which  looked  extremely  well  and 
healthy,  were  in  flower.  Each  seed  had  sent  forth  one  stem,  and 
each  stem,  abundantly  covered  with  leaves,  bore  a  flower. 

On  the  15th  of  August  the  pods  were  ripe ;  no  more  water  was 
given,  and  by  the  end  of  the  month  the  plants  were  dry. 

The  length  of  the  stalks  varied  from  about  three  feet  three  inches 
to  five  feet ;  but  they  were  extremely  slender,  and  the  leaves  not 
more  than  one  third  the  ordinary  size.  The  pods  were  1.3  inch, 
by  from  0.3  to  0.4  of  an  inch  broad.  They  generally  contained  two 
peas  each  ;  one  contained  a  single  pea  only,  hut  this  was  almost 
twice  the  size  of  any  of  the  others. 

In  the  course  of  three  months,  therefore,  these  peas  came  to  per- 
fect maturity — ripe  seeds  were  gathered.  The  analysis  of  the  crop 
which  I  shall  give  by  and  by,  in  connection  with  another  question 
which  we  shall  have  to  discuss,  showed  that  the  harvest  obtained 
under  the  conditions  indicated,  contained  a  considerably  larger  pro- 
portion of  each  of  the  elements  found  than  was  originally  contained 
in  the  seed  from  which  it  sprung. 

Carbon  being  the  predominating  principle  in  plants,  it  is  our  first 
duty  to  inquire  into  the  origin  of  so  much  of  this  element  as  is  as- 
similated in  the  course  of  vegetation. 

Carbon  is  met  with  in  very  small  quantity  in  the  atmosphere  in 
the  state  of  carbonic  acid,  and  as  this  is  one  of  the  most  soluble  of 
the  gases  which  enter  into  the  constitution  of  the  air,  water  always 
contains  a  considerable  quantity  of  it  in  solution.  Carbonic  acid 
may  therefore  be  in  relation  with  plants  by  the  medium  of  the  air 
amidst  which  they  live,  and  of  the  water  which  is  no  less  indispen- 
sable to  their  existence.  We  have  now  to  ascertain  in  what  way 
thit  gas  evolves  and  sets  free  its  carbon  in  favor  of  living  vegetables. 

Bonnet,  having  put  some  fresh  leaves  at  the  bottom  of  a  jar  con- 
taining spring  water,  observed  that  when  exposed  to  the  rays  of  • 
the  sun,  they  gave  off  bubbles  of  air.  He  sought  to  ascertain 
whether  this  disengagement  of  gas  was  due  to  the  leaves,  or  to 
the  liquid  in  which  they  were  contained.  For  the  spring  water,  he 
therefore  substituted  water  deprived  of  its  air  by  boiling,  and  he 
found  that  the  leaves  exposed  to  the  sun's  light  in  this  water,  no 
longer  gave  oflT  any  bubbles  of  air.  Bonnet,  therefore,  concluded 
that  the  gas  which  he  collected  in  his  first  experiment,  proceeded 
from  the  water. 

In  1771,  Priestley  discovered,  that  by  emitting  oxygen,  plants  had 
the  property  of  ameliorating  atmospherical   air,  which  had  been 


ASSIMILATION    OF    CARBON.  35 

ritiated  by  the  respiration  of  animals  or  by  combustion.*  This  un- 
expected discovery  immediately  arrested  the  attention  of  vegetable 
physiologists.  Nevertheless,  Priestley  was  not  yet  master,  so  to 
speak,  of  the  capital  experiment  which  he  had  announced  to  the 
world  of  science.  He  had  not  seized  all  the  circumstances  which 
assure  its  success.  Occasionally  the  leaves  which  were  the  subjects 
of  experiment  did  not  cause  the  disengagement  of  any  gas ;  occa- 
sionally, too,  the  air  disengaged,  far  from  being  oxygen — far  from 
ameliorating  the  atmosphere,  was  found  to  be  carbonic  acid  gas.  It 
was  Ingenhousz  who  made  out  the  influence  of  the  solar  light  upon 
the  phenomenon  in  question.  He  proved,  by  a  vast  number  of  dis- 
tinct experiments,  that  leaves  exhale  oxygen  when  they  are  exposed 
to  the  light  of  the  sun.  He  perceived,  moreover,  that  in  the  dark 
they  vitiate  the  air,  rendering  it  improper  for  respiration  and  com- 
bustion, f 

But  the  origin  of  the  oxygen  disengaged  from  water  by  leaves 
exposed  to  the  light  of  the  sun  still  remained  to  be  discovered.  It 
was  Sennebier  who  took  this  important  step,  by  showing  that  it  was 
to  the  carbonic  acid  generally  contained  in  water  that  leaves  ex- 
posed to  the  sun's  light  owed  their  faculty  of  evolving  oxygen  gas. 
With  this  interesting  fact,  it  was  easy  to  render  an  account  of  all 
the  anomalies  that  had  been  successively  announced  :  boiled  water, 
as  Bonnet  had  observed,  could  not  afford  any  air,  and  spring  water 
should  usually  give  more  than  river  water,  as  Ingenhousz  had  no- 
ticed, for  the  simple  reason  that  boiled  water  neither  contains 
carbonic,  acid  gas  nor  any  other  kind  of  air ;  and  that  well  water 
generally  contains  a  larger  quantity  of  carbonic  acid  in  solution  than 
river  water. 

In  giving  the  grand  features  in  the  history  of  this  brilliant  discov- 
ery of  the  eighteenth  century,  it  may  be  said  that  Bonnet  was  the 
first  who  observed  the  phenomenon  of  the  gaseous  evolution  effected 
by  the  leaves  of  vegetables  :|  that  Priestley  announced  that  the  gas 
disengaged  was  oxygen  ;  that  Ingenhousz  demonstrated  the  neces- 
sity of  the  solar  light  to  the  production  of  the  phenomenon :  finally, 
that  it  was  Seimebier,  to  whom  was  reserved  the  honor  of  showing 
that  the  oxygen  gas  obtained  under  these  circumstances  is  the  pro- 
duct of  the  decomposition  of  carbonic  acid. 

It  was,  however,  matter  of  supreme  interest  to  study  this  decom- 
position of  carbonic  acid  in  its  last  details.  It  was  imperative,  for 
instance,  to  ascertain  what  relation  existed  between  the  volume  of 
the  oxygen  disengaged  and  the  volume  of  the  carbonic  acid  decom- 
posed. This  was  admirably  accomplished  by  M.  Theodore  de  Saus- 
sure  in  a  long  series  of  remarkable  experiments,  of  which  I  shall  here 
endeavor  briefly  to  state  the  main  results. 

The  conclusion  which  follows  naturally  from  the  discovery  of 
Sennebier,  was  that  carbonic  acid  exercised  a  favorable  influence  on 
vegetation  by  supplying  plants  with  the  carbon  which  enters  into 

*  Experiments  and  Observations,  vol.  ii. 

t  Experiments  on  Vegetables. 

i  Sur  I'usage  des  feuilles  dans  tea  plantes,  p.  3! 


86  EVOLUTION    AND    GROWTH. 

their  constitution.  Percival  ascertaini^d  by  direct  experiment  thi 
accuracy  of  this  inference  by  placintj  plants  in  a  current  of  atmo 
spheric  air,  mixed  with  a  pretty  large  proportion  of  this  gas.  By 
means  of  a  comparative  experiment,  he  saw  that  a  plant  in  such 
circumstances  made  much  greater  progress  than  one  subjected  to  a 
current  of  ordinary  air.*  The  researches  of  Saussure,  in  confirm- 
ing in  all  respects  those  of  his  predecessors,  added  this  farther  very 
important  fact :  that  to  act  beneficially  upon  vegetables  the  carbonic 
acid  must  be  mixed  with  oxygen. 

Under  a  bell  glass  of  the  capacity  of  398  cubic  inches,  placed  over 
mercury,  with  a  delicate  film  of  water  swimming  on  its  surface,  he 
introduced  three  young  peas,  which  displaced  about  y^y  of  the  in- 
cluded air.  The  atmosphere  was  composed  of  common  air  and 
carbonic  acid  gas  in  different  proportions. 

The  experiments  were  conducted  successively  in  the  sunshine  and 
in  the  shade.  In  the  sun,  the  apparatus  received  daily  the  direct 
action  of  the  light  during  five  or  six  hours  :  v^hen  the  light  was  loo 
vivid  it  was  somewhat  lessened  by  shading.  In  the  sunlight  the 
plants  lived  for  several  days  in  an  atmosphere  composed  of  equal 
parts  of  air  and  carbonic  acid ;  they  then  faded.  But  they  died 
much  more  speedily  in  atmospheres  which  contained  two-thirds,  or 
three-fourths,  or  a  fortiori  which  consisted  entirely  of  carbonic  acid. 
The  young  plants  throve  decidedly  when  the  atmosphere  contained 
about  —^th  of  carbonic  acid  ;  their  growth  was  evidently  more  vigor- 
ous here  than  it  was  in  simple  air ;  and  at  the  conclusion  of  one  ex- 
periment which  extended  over  ten  days,  almost  the  whole  of  the 
carbonic  acid  was  found  replaced  by,  or  changed  into  oxygen  :  the 
peas  had  assimilated  the  carbon. 

The  smallest  quantity  of  carbonic  acid  added  to  the  air,  was 
found  injurious  to  the  plants  when  they  were  kept  in  the  shade. 
Young  peas  lived  only  six  days  under  such  circumstances,  when 
the  atmosphere  around  them  consisted  of  a  quarter  of  its  volume  of 
carbonic  acid.  They  lived  ten  days  when  the  proportion  of  this 
gas  did  not  exceed  a  twelfth ;  but  then  they  scarcely  grew  at  all  in 
the  mixture ;  they  certainly  made  much  less  progress  than  they 
would  have  done  in  common  air.  Saussure  concluded,  from  these 
experiments,  that  carbonic  acid  was  useful  to  growing  vegetables 
only  when  present  along  with  oxygen,  and  that  it  ceases  to  be 
so  when  the  atmosphere  contains  more  than  ^^\h  of  its  volume  of 
the  gas. 

To  determine  the  proportion  of  oxygen  set  at  liberty  during  the 
decomposition  of  carbonic  acid  by  plants,  Saussure  composed  an 
atmosphere  nf  common  air  and  carbonic  acid,  the  latter  in  the  pro- 
portion of  0.075;  the  mixture  was  confined  under  a  bell-glass  of 
the  capacity  of  5.746  litres  or  10.112  pints,  standing  over  mercurj 
as  in  the  former  experiments.  Seven  plants  of  the  periwinkle  were 
introduced  into  the  apparatus,  their  roots  dipping  into  15  cub.  centim. 
or  5.895  cub.  in.  of  water — the  water  was  limited  as  much  as  possible^ 

*  Maacbcster  Mcmcirs,  vol.  U 


DECOMPOSITION    OF    CARBONIC    ACID.  37 

in  order  that  the  absorption  of  carbonic  acid,  which  must,  of  course, 
take  place,  might  be  thrown  out  of  ihe  reckoning.  The  experiment 
was  continued  for  six  days,  during  which  the  plants  received  the 
direct  rays  of  the  sun  from  five  to  eleven  o'clock  in  the  morning. 
On  the  seventh  day,  the  plants  were  withdrawn.  They  had  pre- 
served their  freshness.  All  the  corrections  made  for  temperature 
and  pressure,  the  volume  of  the  atmosphere  in  which  they  had  lived 
was  not  found  changed  by  more  than  about  20  cubic  centimetres, 
7.8  c.  in.,  a  quantity  which  is  within  the  possible  errors  of  compu- 
tation ;  but  the  composition  of  the  air  had  undergone  very  notable 
changes  :  the  carbonic  acid  had  disappeared,  and  the  eudiometer 
proclaimed  0.24  of  oxygen  instead  of  the  0.21  which  it  contained 
originally.* 

RESULTS  OF  THE  EXPERIMENTS. 

c.  inches.  Azote.  Oxygen.    Garb.  acid. 

Pe/ore :  Volume  of  atmosphere 2257  containing  1650  438-5        169-3 

^fter:  "  "  2257  "  1704  553 0_^ 

0  +54  +14-8    —169-3 

The  periwinkles,  consequently,  had  caused  169.3  cubic  inches  of 
carbonic  acid  to  disappear,  and  given  off  upwards  of  one  hundred 
and  fourteen  cubic  inches  of  oxygen.  Had  the  whole  oxygen  of  the 
carbonic  acid  been  set  at  liberty,  this  volume  would  have  been  pre- 
cisely equal  to  that  of  the  acid  gas  decomposed  ;  but  as  no  more 
than  one  hundred  and  fourteen  cubic  inches  of  oxygen  were  obtained, 
it  must  be  inferred  that  the  periwinkles  had  fixed  54.6  cubic  inches 
of  this  gas. 

This  is  the  conclusion,  indeed,  to  which  M.  de  Saussure  came, 
and  subsequent  experiments  have  confirmed  its  accuracy.  The 
following  table  contains  a  summary  of  five  experiments  that  were 
instituted  : 

C.  inches.  c.  inches. 

Exp.l.  Carbonic  acid  disappearing. ••169.3    Oxygen  disengaged.. •  114-7 

Azote  disengaged- ••  •  •  54-6 
169-3 

Exp.  2.        "  "  "         •••121.4    Oxygen  disengaged. . .      88 

Azote  disengaged  •  •  •  •       33 
121 

Exp.  3.       "  "  "  ....58-5    Oxygen  disengaged  —  47.5 

Azote  disengaged 8-2 

55.7 

Exp.  4.       "  "  "  ...120-2    Oxygen  disengaged — 96-6 

Azote  disengaged  . . ...  7-8 

104.4 
Exp.5.        u  u  u  ....72.3    Oxygen  disengaged.... 49.5 

Azote  disengaged 22.4 

There  is  one  remark  which  it  is  impossible  to  avoid  making  in  sur- 
veying this  table  ;  it  is  to  the  effect,  that  the  azote  disengaged  rep- 

*  Saussure,  Kccherches  chimiques,  p  40 
4 


88  EVOLUTION    AND    GROWTH. 

resents  almost  exactly  the  volume  of  oxygen  which  it  would  be 
necessary  to  add,  in  order  that  the  oxygen  collected  should  represent 
the  whole  of  that  which  entered  into  the  constitution  of  the  carbonic 
acid  decomposed.  It  is  probable  that  the  excess  of  azote  wliich  ap- 
peared in  all  these  experiments  was  present  in  principal  part  in  the 
air  contained  and  condensed  within  the  interstices  of  the  plants,  or 
held  in  solution  in  the  water  which  bathed  their  roots.  It  would  be 
difficult  to  assign  it  any  other  origin  ;  such,  for  instance,  as  that 
from  changes  in  the  azotized  principles  of  the  plants  that  were  the 
subject  of  experiment.  In  his  first  experiment,  in  fact,  M.  de  Saus- 
sure  fixes  the  weight  of  the  dry  matter  of  the  seven  periwinkle 
plants  at  41.6  grains.  Now,  from  numerous  determinations  of  azote 
which  I  have  had  occasion  to  make  in  regard  to  plants  of  very  dif- 
ferent ages  and  species,  I  think  I  can  say  that  these  periwinkles, 
taken  as  dry,  did  not  contain  more  than  .385  of  azote ;  this,  in  ref- 
erence to  the  weight  assumed  by  M.  de  Saussure,  would  be  1.042 
grs.  or  20.8  cubic  inches  of  azote;  and  the  volume  of  azote  disen- 
gaged in  this  first  experiment  was  54.6  cubic  inches.  It  is  proper 
further  to  observe,  that  the  state  of  health  which  the  plants  pre- 
sented on  the  conclusion  of  the  experiment  does  not  allow  us  to  sup- 
pose a  total  decomposition  of  the  azotized  matters  which  entered 
into  their  constitution.  These  various  considerations  lead  us  to  in- 
fer that  the  excess  of  azote  collected  must  have  been  displaced  by 
oxygen.  We  are,  therefore,  at  liberty  to  presume,  from  the  experi- 
ments now  referred  to,  that  the  volume  of  oxygen  produced  probably 
represents  the  volume  of  carbonic  acid  decomposed. 

The  necessity  of  oxygen  gas  in  the  decompounding  action  which 
plants  exposed  to  the  light  exert  so  energetically  upon  carbonic  acid, 
leads  us  to  study  particularly  the  phenomena  which  oxygen  exhibits 
in  connection  with  growing  plants.  When  a  number  of  freshly 
gathered  and  healthy  leaves  are  placed  during  the  night  under  a  bell- 
glass  of  atmospheric  air,  they  condense  a  portion  of  the  oxygen  ; 
the  volume  of  the  air  diminishes,  and  there  is  a  quantity  of  free  car- 
bonic acid  formed,  generally  less  than  the  volume  of  oxygen  which 
l.is  disappeared.  If  the  leaves  which  have  absorbed  this  oxygen 
during  their  stay  in  the  dark,  be  now  exposed  to  the  sun's  light,  they 
restore  it  nearly  in  equal  quantity,  so  that,  all  corrections  made,  the 
atmosphere  of  the  bell-glass  returns  to  its  original  composition  and 
"volume. 

Leaves  in  general  have  the  same  effect  when  they  are  placed  alter- 
nately in  the  dark  and  in  the  light;  there  is,  however,  a  very  obvious 
difference  in  the  intensity  with  which  the  phenomenon  is  produced, 
according  to  the  nature  of  the  leaves.  The  quantity  of  carbonic 
acid  formed  during  the  night  is  by  so  much  the  less,  as  the  leaves 
are  more  fleshy,  thicker,  and  therefore  more  watery.  The  green 
matter  of  fleshy  leaved  plants,  of  the  cactus  opuntia,  to  quote  a  par- 
ticular instance,  does  not  produce  any  sensible  quantity  of  carbonic 
acid  in  the  dark  :  but  these  leaves  condense  oxygen,  and  exhale  it 
again  like  those  which  are  less  fleshy,  when  they  are  brought  into 
he  sun,  after  having  been  kept  for  some  time  in  the  dark. 


DECOMPOSITION    OF    CARBONIC    ACID.  89 

Saussure  applied  the  names  of  inspiration  and  expiration  of  plants 
to  these  alternate  effects,  led  by  the  analogfv — somewhat  remote,  it 
must  be  confessed — which  the  phenomenon  presents  with  the  respi- 
ration of  animals. 

The  inspiration  of  leaves  has  certain  limits  ;  in  prolonging  their 
stay  in  the  dark,  the  absorption  becomes  less  and  less :  it  ceases 
entirely  when  the  leaves  have  condensed  about  their  own  volume  of 
oxygen  gas.  And  let  it  not  be  supposed  that  the  nocturnal  inspira- 
tion of  leaves  is  the  consequence  of  a  merely  mechanical  action, 
comparable,  for  example,  to  that  exerted  by  porous  substances  gen- 
erally upon  gases.  The  proof  that  it  is  not  so  is  supplied  by  the 
fact  that  the  same  effects  do  not  follow  when  leaves  are  immersed  in 
carbonic  acid,  hydrogen,  or  azote.  In  such  circumstances  there  is 
no  appreciable  diminution  of  the  atmosphere  that  surrounds  the 
plant.  The  primary  cause  of  the  inspiration  of  oxygen  by  the 
leaves  of  living  plants  is,  therefore,  obviously  of  a  chemical  nature. 

With  the  facts  which  have  just  been  announced  before  us,  it  seems 
very  probable  that  during  the  nocturnal  inspiration,  the  carbonic  acid 
which  appears  is  formed  at  the  cost  of  carbon  contained  in  the  leaves, 
and  that  this  acid  is  retained  either  wholly  or  in  part,  in  proportion 
as  the  parenchyma  of  the  leaf  is  more  or  less  plentifully  provided 
with  water.  A  plant  that  remains  permanentl};  in  a  dark  place, 
exposed  to  the  open  air,  loses  carbon  incessantly  :  the  oxygen  of  the 
atmosphere  then  exerts  an  action  that  only  terminates  with  the  life 
of  the  plant :  a  result  which  is  apparently  in  opposition  to  what  takes 
place  in  an  atmosphere  of  limited  extent.  But  it  is  so,  because  in 
the  free  air  the  green  parts  of  vegetables  can  never  become  entirely 
saturated  with  carbonic  acid,  inasmuch  as  there  is  a  ceaseless 
interchange  going  on  between  this  gas,  and  the  mass  of  the  surround- 
ing atmosphere  ;  there  is,  then,  incessant  penetration  of  the  gases, 
as  it  is  called.  There  is  a  kind  of  slow  combustion  of  the  carbon 
of  a  plant  which  is  abstracted  from  the  reparative  influence  of  the 
light. 

The  oxygen  of  the  air  also  acts,  but  much  less  energetically,  upon 
the  organs  of  plants  that  do  not  possess  a  green  color. 

The  roots  buried  in  the  ground  are  still  subjected  to  the  action  of 
this  gas.  It  is  indeed  well  known,  that  to  do  their  office  properly, 
the  soil  must  be  soft  and  permeable,  whence  the  repeated  hoeings 
and  turnings  of  the  soil,  and  the  pains  that  are  taken  to  give  access 
to  the  air  into  the  ground  in  so  many  of  the  operations  of  agricul- 
ture. The  roots  that  penetrate  to  a  great  depth,  such  as  those  of 
many  trees,  are  no  less  dependent  on  the  same  thing  ;  the  moisture 
that  reaches  them  from  without  brings  them  the  oxygen  in  solution, 
which  they  require  for  their  development.  It  is  long  since  Dr. 
Stephen  Hales  showed  that  the  interstices  of  vegetable  earth  still 
contained  air  mingled  with  a  very  considerable  proportion  of  oxygen. 
The  roots  of  vegetables,  moreover,  appear  generally  to  be  stronger 
and  more  numerous  as  they  are  nearer  the  surface.  In  tropical 
countries  various  plants  have  creeping  roots  which  often  acquira 
dimensions  little  short  of  those  of  the  trunk  they  feed. 


40  EVOLUTIOiS  AND  GROWTH. 

If  a  root  detached  from  the  stern  be  introduced  under  a  bell-glasa 
full  of  oxygen  gas,  the  volume  of  the  gas  diminishes,  carbonic  acid 
is  formed,  of  which  a  portion  only  mingles  with  the  gas  of  the 
receiver,  a  certain  quantity  being  retained  hy  the  moisture  of  the 
root.  The  volume  of  the  gas  thus  retained  is  always  less  than  that 
of  the  root  itself,  however  long  the  experiment  may  be  cortinued. 
In  these  circumstances,  whether  in  the  shade  oi  the  sun,  roots  act 
precisely  as  leaves  do  when  kept  in  the  dark.  Roots  still  connected 
with  their  stems,  give  somewhat  different  results. 

When  the  experiment  is  made  with  the  stem  and  the  leaves  in  the 
free  air,  while  the  roots  are  in  a  limited  atmosphere  of  oxygen,  they 
then  absorb  several  times  their  own  volume  of  this  gas.  This  is  be- 
cause the  carbonic  acid  formed  and  absorbed  is  carried  into  the  general 
system  of  the  plant,  where  it  is  elaborated  by  the  leaves,  if  exposed  to 
the  same  light,  or  simply  exhaled  if  the  plant  be  kept  in  the  dark. 

The  presence  of  oxygen  in  the  air  which  has  access  to  the  roots 
is  not  merely  favorable  ;  it  is  absolutely  indispensable  to  the  exer- 
cise of  their  functions.  A  plant,  the  stem  and  leaves  of  which  are 
in  the  air,  soon  dies  if  its  roots  are  in  contact  with  pure  carbonic 
acid,  with  hydrogen  gas,  or  azote.  The  use  of  oxygen  in  the  growth 
of  the  subterraneous  parts  of  plants,  explains  wherefore  our  annual 
plants,  which  have  largely  developed  roots,  require  a  friaWe  and 
loose  soil  for  their  advantageous  cultivation.  This  also  enables  us 
to  understand  wherefore  trees  die,  when  their  roots  are  submerged 
in  stagnant  water,  and  wherefore  the  effect  of  submersion  in  general 
is  less  injurious  when  the  water  is  running,  such  water  always  con- 
taining more  air  in  solution  than  that  which  is  .stagnant. 

The  woody  parts,  the  fruit,  and  those  organs  of  plants  in  general 
which  have  not  a  green  color,  stand  in  the  same  relations  to  oxygen 
as  the  roots :  they  merely  change  this  gas  into  carbonic  acid,  which 
is  then  transported  to  the  plant  at  large,  to  suffer  decomposition  by 
the  green  parts.  In  this  action  we  observe  a  displacement,  a  kind 
of  translation  of  the  carbon  of  the  lower  to  the  upper  parts  of 
plants. 

The  decomposition  of  carbonic  acid  by  plants  admitted,  we  have 
still  to  examine  whether,  in  the  phenomena  of  vegetation,  the  leaves 
decompose  the  carbonic  acid  of  the  atmosphere  directly,  or  the  acid 
gas,  previously  dissolved  in  the  water,  which  moistens  the  ground, 
be  conducted  by  the  way  of  absorption  into  the  tissues  of  vegetables, 
there  to  suffer  decomposition.  The  quantity  of  carbonic  acid  con- 
tained in  the  air  is  so  small,  and  the  growth  of  plants,  on  the  con- 
trary, is  often  so  rapid,  that  it  might  reasonably  be  suspected  that 
the  carbon  which  they  require  was  introduced  in  great  part  by  this 
way  of  absorptitm.  In  that  series  of  beautiful  experiments  in  '.vlijcii 
M.  Saussure  exposed  plants  to  the  influence  of  atmosphere.s  more 
or  less  charged  with  carbonic  acid,  the  water  in  which  their  routs 
were  plunged  was  in  contact  with  the  mixed  atmospheres.  It  was 
therefore  possible  that  the  carbonic  acid  gas  entered  the  vegeiablos 
in  the  solution  by  the  roots. 

Sennebier  made  an  experiment  to  show  that  leaves  decompose 


DECOMPOSITION    OF    CARBONIC    ACID.  41 

both  the  carbonic  acid  which  is  in  contact  with  them  externally,  and 
that  wliich  is  dissolved  in  the  water  absorbed  by  their  woody  tissue. 
He  took'  two  branches  of  a  peach-tree,  and  introduced  them  into  a 
couple  of  bell-glasses  filled  with  water  from  the  same  spring.*  The 
lower  snd  of  each  branch  dipped  into  a  flask.  One  of  the  flasks 
was  filled  with  water  charged  with  carbonic  acid  ;  the  other  con- 
tained air :  the  two  bell-glasses  were  exposed  to  the  light.  Tiie 
leaves  of  the  branch  whose  extremity  dipped  into  the  solution  of 
carbonic  acid,  disengaged  99.4  cubic  inchi  t  of  oxygen  gas  undei 
the  bell  which  covered  it :  the  leaves  of  ihu  uiher  branch  only  pro- 
duced 52.2  cubic  inches  in  the  same  lime. 

This  experiment  does  not  perhaps  afford  all  the  sufficient  evi- 
dence of  the  decomposition  of  gaseous  carbonic  acid  as  it  occurs  in 
the  atmosphere,  and  mixed  with  a  great  mass  of  air.  It  appears, 
however,  that  the  leaves  of  plants  have  the  power  of  decomposing 
the  gaseous  carbonic  acid  which  is  mixed  with  the  air,  and  that 
even  with  surprising  rapidity. 

In  the  summer  of  1840, 1  introduced  into  a  balloon  of  the  capacity 
of  about  twelve  quarts  and  a  half,  and  furnished  with  three  tubulures 
or  openings,  the  branch  of  a  vine  in  full  growth  and  bearing  twenty 
leaves.  The  woody  part  of  the  branch  was  fixed  by  means  of  a  collar 
of  caoutchouc  to  the  lower  orifice  of  the  balloon  ;  a  fine  tube,  intend- 
ed to  establish  a  communication  between  the  interior  of  the  vessel 
and  the  outer  air,  was  introduced  into  the  superior  tubulure  ;  the 
lateral  opening  communicated  by  means  of  a  tube  with  an  apparatus 
which  measured  with  great  accuracy  the  quantity  of  carbonic  acid 
contained  in  the  atmosphere. 

In  this  experiment  the  air,  before  reaching  the  apparatus  for 
measuring  the  carbonic  acid,  passed  through  the  great  balloon  con- 
taining the  vine  branch.  The  rate  with  which  the  air  passed  through 
the  apparatus  was  regulated  by  the  flow  of  an  aspirator,  and  was  at 
the  rate  of  about  twelve  quarts  per  hour. 

The  apparatus  was  exposed  to  the  sun  ;  the  experiment  beginning 
at  eleven  and  finishing  at  three  o'clock. 

Ir  one  experiment  it  was  found,  all  corrections  made,  that  the  at- 
mospheric air,  after  having  passed  through  the  balloon,  contained  in 
volume  0.0002  of  carbonic  acid  gas ;  the  air  of  the  adjoining  court 
contained  at  the  same  moment  0.00045  of  carbonic  acid. 

In  another  experiment,  the  air,  after  having  passed  over  the  leaves, 
contained  but  0.0001  of  carbonic  acid  ;  the  air  of  the  court  contsin- 
ing  0.0004  of  the  same  gas.  In  traversing  the  space  in  which  the 
vine  branch,  exposed  to  the  light  of  the  sun,  was  included,  therefore 
the  air  was  deprived  of  three  fourths  of  the  whole  quantity  of  car- 
bonic acid  which  it  contained. 

In  operating  with  the  same  apparatus  during  the  night,  opposite 
results  were  obtained  ;  the  air  in  traversing  the  balloon  generally 
acquired  a  quantity  of  carbonic  acid,  the  double  of  that  which  the 
atmosphere  contained  at  the  same  moment. 

•  This  was  common  water  containing  carbonic  acid 

4* 


42  EVOLUTION    AND    GROWTH. 

I  conceive  that  it  is  by  such  a  method  as  this,  that  the  genera, 
phenomena  of  vegetable  respiration  in  plants  still  connected  with  the 
soil  ought  to  be  studied. 

The  experiments  which  I  have  now  related  must  satisfy  every 
one,  that  the  leaves  of  living  plants  actually  assimilate  the  carbon 
which  occurs  in  our  atmosphere  in  the  state  of  carbonic  acid  ;  they 
also  explain  the  well-known  fact  that  plants  thrive  better  in  air  that 
is  in  motion,  and  frequently  renewed,  than  in  a  perfect  calm. 

From  all  we  have  seen  up  to  this  time,  then,  w^e  feel  authorized 
to  conclude  that  the  greater  proportion  if  not  the  whole  of  the  carbon 
which  enters  into  the  constitution  of  vegetables  is  derived  from  the 
carbonic  acid  of  the  atmosphere.  The  experiments  cited,  show- 
how  the  vital  force  acts  at  first  on  the  oxygen  of  the  air  during  ger- 
mination, and  next  upon  its  carbonic  acid  during  vegetation  properly 
so  called.  But  in  none  of  the  experiments  which  have  been  quoted, 
have  we  seen  any  thing  which  could  lead  us  to  suspect  that  the 
azote  of  the  atmosphere  was  absorbed  in  sensible  quantity. 

It  is  true,  indeed,  that  at  one  time  Priestley,  and  after  him,  Tn- 
genhousz,  thought  that  they  had  observed  an  absorption  of  azote 
during  the  growth  of  plants  in  confined  atmospheres.  But  the  ex- 
periments which  have  been  since  performed  by  Saussure  have  not 
confirmed  their  conclusions  upon  this  point.  Saussure  even  thought 
that  he  had  perceived  a  slight  exhalation  of  azote. 

Nevertheless,  the  presence  of  azote  in  vegetables  being  incon- 
testable, and  the  assimilation  of  this  principle  during  their  growth 
being  in  some  sort  demonstrated  by  the  fact  that  seeds  are  multiplied, 
physiologists  were  led  to  imagine  that  the  azote  was  derived  from 
ihe  soil.  And  in  nature,  indeed,  the  growth  of  a  plant  does  not  take 
place  at  the  sole  c«)st  of  water  and  the  atmosphere.  The  roots 
w^hich  attach  it  to  the  earth  there  also  find  elements  of  nutrition. 
In  ordinary  circumstances  the  growth  of  a  plant  takes  place  by  the 
simultaneous  concurrence  of  the  food  which  the  roots  encounter  in 
the  ground,  and  that  which  the  leaves  abstract  from  the  gaseous 
elements  of  the  air.  As  it  is  further  acknowledged  that  the  food 
which  is  supplied  by  the  soil  is  for  the  most  part  azotized,  manures 
have  therefore  been  regarded  as  the  principal  and  even  as  the  ex- 
clusive source  of  the  azote  which  is  met  with  in  vegetables.  The 
observations  of  Hermbstadt,  in  showing  that  the  grain  which  was 
grown  under  the  influence  of  the  most  highly  azotized  manures 
contained  the  largest  quantity  of  gluten,  gave  a  certain  force  to  this 
view.  Nevertheless,  there  are  facts  well  established  in  agriculture 
which  induce  us  to  think  that  in  many  cases  vegetables  find  in  the 
atmosphere  a  part  of  the  azote  which  is  necessary  to  their  con- 
stitution. 

The  majority  of  crops  exhaust  the  soil ;  but  there  are  still  some 
n'hich  render  it  more  fertile.  We  shall  see,  by  and  by,  when  treat- 
ing of  the  rotation  of  crops,  that  if,  after  having  cut  a  field  of  trefoil 
once,  the  second  crop  be  ploughed  down,  new  fertility  is  communicated 
to  the  ground,  in  spite  of  the  considerable  mass  of  forage  which  had 
previously  been  taken  from  it.     It  appears  therefore  evident,  that 


ASSIMILATION    OF    AZOTE.  >  43 

in  ploughing  down  this  second  crop  we  restore  such  a  quantity  of 
organic  or  organizable  matter,  that,  all  things  taken  into  account, 
the  ground  actually  receives  more  from  the  atmosphere  than  was 
taken  away  from  it  in  the  first  cutting. 

The  latest  experiments  of  physiologists  would  seem  to  show  that 
plants  merely  take  carbon  from  the  air,  and  appropriate  the  elements 
of  water.  But  the  ideas  which  are  now  generally  adopted  in  regard  to 
the  active  principle  of  manures  make  it  difficult  to  conceive  that  the 
soil,  by  receiving  nou-azotized  matters  only,  could  acquire  the  degree 
of  fertility  whic'h  is  certainly  obtained  from  The  cultivation  of  •hose 
crops  that  are  called  ameliorating^  a  fertility  which  enables  us  to 
follow  these  crops  with  others,  rich  in  azotized  principles. 

There  is  therefore  reason  for  believing  that  the  ploughing  in  of 
certain  green  crops,  and  fallowing,  are  not  effectual  merely  by  in- 
troducing carbon,  hydrogen,  and  oxygen,  but  azote  also  into  the 
soil.  And  it  is  absolutely  necessary  that  this  should  be  so,  in  order 
that  the  fertility  of  those  lands  may  be  maintained  which,  from  theii 
position,  can  receive  no  manures  from  without.  Let  us  take,  for 
example,  a  farm  laid  out  for  the  growth  of  white  crops,  and  the 
rearing  of  cattle.  Every  year  there  is  an  exportation  of  grain,  of 
flesh,  and  of  the  produce  of  the  dairy ;  that  is  to  say,  there  is  inces- 
sant exportation  without  any  perceptible  importation  of  azotized 
matter.  Nevertheless,  the  soil  maintains  its  fertility  ;  its  losses  are 
repaired  by  the  principles  which,  in  a  good  system  of  cultivation, 
pass  from  the  atmosphere  into  the  earth  ;  and  among  the  number  of 
these  fertilizing  principles  it  is  beyond  all  question  that  azote  must 
be  present,  in  order  that  so  much  of  this  element  as  has  been  ex- 
ported may  be  replaced. 

The  best  established  facts  in  agriculture,  therefore,  concurred  in 
showing  that  azote  is  among  the  number  of  the  elements  that  are 
fixed  by  plants  during  their  growth.  Still,  as  this  truth  had  not  been 
proved  by  the  experiments  of  physiologists,  the  question  had  to  be 
considered  as  yet  undecided.  It  was  with  the  hope  of  clearing  up 
every  thing  in  connection  with  it  that  I  undertook  the  series  of  ex- 
periments, the  chief  features  of  which  I  shall  now  detail.* 

I  had  necessarily  to  follow  a  method  of  inquiry  different  from  any 
which  had  yet  been  taken  ;  I  had  no  chance  of  arriving  at  more  de- 
finite results  than  those  which  had  been  already  come  to,  had  I  cho- 
sen the  old  line  of  investigation.  I  therefore  called  in  the  aid  of 
elementary  analysis,  with  a  view  of  romparing  the  composition  of 
the  seed  with  the  composition  of  the  harvest  produced  from  it,  at  the 
sole  cost  of  water  and  the  air.  By  proceeding  in  this  way  I  believed 
that  the  problem  was  capable  of  solution  :  without  flattering  my- 
self that  I  have  completely  resolved  it,  I  conceive  that  something 
has  been  done  in  the  right  direction.  The  subject  is  one  of  the  most 
delicate  imaginable,  and  he  who  enters  it  requires  indulgence. 

For  soil,  I  made  use  of  burned  clay  or  silicious  sand  freed  from 
all  organic  matter  by  proper  calcination.     In  this  soil,  moistened 

♦  Boussi- garolt,  Annates  de  chimie  et  tie  physique,  f  Ixvii.  p.  5,  2*  86rie,  aan6e  1838 


44  EVOLUTION  AND  GKOWTH. 

with  distilled  water,  were  sown  the  seeds  whose  weig^ht  was  known 
By  a  number  of  preliminary  trials,  the  quantity  of  moisture  which 
seed  of  t!te  same  kind,  of  the  same  growth,  and  taken  at  the  same 
moment,  lost  hy  drying,  commenced  in  the  stove  and  finished  in  an 
oil-hath,  ?-t  110"  C.  (230'  Fahr.)  was  ascertained.  The  porcelain 
vessels,  in  which  the  experiment  was  conducted,  were  placed  in  a 
glass  houpe  at  the  end  of  a  large  garden.  During  the  whole  term, 
the  windows  were  kept  closed ;  but  the  sun  shone  on  the  house  all 
day.  To  remove  the  produce,  the  vessels  were  dried  by  a  gentle 
heat.  The  roots  of  the  plants  then  came  out  readily  ;  to  free  them 
completely  from  any  adhering  sand,  they  were  moved  about  in  a  little 
distilled  water,  but  never  rubbed  or  bruised,  for  fear  of  loss  ;  it  seem- 
ed even  preferable  to  leave  a  little  sand  adhering.  The  harvest  was 
then  drieii  in  the  stove,  so  that  it  might  be  powdered  ;  and  the  com- 
plete desiccation  was  effected  in  the  oil-bath  in  vacuo. 

In  ascertaining  previously  by  muneration  the  weight  cf  the  ashes 
contained  in  the  seed,  that  of  the  produce,  freed  from  all  saline  and 
earthy  matter,  became  exactly  known. 

Elementary  analysis  then  proclaimed  the  composition  of  the  pro- 
duce ;  and  it  was  only  necessary  now  to  compare  it  with  the  com- 
position of  the  seed,  to  have  ascertained  the  proportion  and  the 
nature  of  the  elements  which  had  been  assimilated  during  the  vege- 
tation. 

FIRST  EXPERIMENT. 

CULTURE    OF    RED    CLOVER   DURING    THREE    MONTHS. 

In  the  beginning  of  August  a  quantity  of  seed  was  sown,  which, 
being  dry  and  free  from  ashes,  would  have  weighed  1.586  gramme, 
or  24.48  grs.  troy.  The  crop  presented  a  very  good  appearance ; 
the  clover  was  from  three  to  three  and  a  half  inches  in  height.  The 
largest  leaves  could  be  included  in  a  circle  of  about  two  inches  in 
diameter.  The  length  of  the  roots  varied  between  two  and  four 
inches.  Dried  and  bruised,  the  color  of  the  produce  was  a  deep 
green. 

The  plant  gathered  quite  dry,  and  supposed  free  from  ash,  weighed 
4.106  grammes,  or  63.38  grs.  troy  ;  analysis  showed  it  to  consist  of— 

In  the  Seed.  In  the  Produce 

Carbon.   50.8  50.7 

Hydrogen  6.0  6.6 

Azote 7.2  3.8 

Oxygen .36.0  _38.9 

100.0  100.0 

RESULTS. 

Carbon.     Hvi1ro?cn.  Oxr^en.      Azote. 

5M.48  grs.  ircy  containing  after  the  analysis         12.44      1.466        8.81">      1.759 
63.38  "  "  "  ....     32.141      4.183      24.ir>5      2.408 

38.90  =  grs'.  during  cultivation  ....  +19.70  +2.717  +15.840  +0.049 

Thus,  in  the  course  of  three  months,  the  elementary  matter  of  the 
4eed  had  nearly  doubled,  and  the  azote  of  the  plants  gathered  shows 


ASSIMILATION  OF  ELEMENTS.  4S 

an  excess  of  0.042  gramme,  or  0.649  grs.  troy,  above  the  azote  of  the 
seed  sown. 

SECOND   EXPERIMENT. 

GROWTH  OF  PEAS. 

Five  peas,  very  nearly  of  the  same  weight,  and  together  weighing 
1.211  gramme,  or  18.69  grs.  troy,  were  planted  on  the  9th  of  May,  in 
a  soil  of  recently  burned  clay  in  rough  powder.  On  the  16th  of  July, 
the  plants  began  to  bloom,  each  pea  having  furnished  a  stem  bearing 
a  single  flower. 

On  the  15th  of  August  the  pods  were  quite  ripe  ;  the  stems  were 
then  from  39  to  40  inches  in  height.  The  leaves  were  smaller  than 
those  of  the  same  peas  grown  in  manured  earth.  The  length  of  the 
pods  was  about  1.27  inch,  by  a  breadth  of  about  0.43  inch.  Four 
of  these  pods  each  contained  two  seeds ;  the  fifth  had  only  one,  but 
it  was  much  longer  than  any  of  the  others. 

The  nine  peas  gathered  and  dried  in  the  sun,  weighed  1.674  gram., 
or  25.84  grs.  ;  after  desiccation  in  vacuo,  at  110°  C,  (230'"  F.,)  they 
weighed  1.507  gram.,  or  23.26  grs.  troy  ;  on  combustion  they  yielded 
0.9  per  cent,  of  residue. 

The  roots,  the  stems,  the  pods,  and  the  leaves,  dried  at  230°  F., 
weighed  3.314 gram.,  or  51.16 grs.  troy;  and  by  combu.*tion  gave 
10  3  per  cent,  of  ashes. 

As  the  result  of  several  experiments,  it  was  ascertained  that  peas, 
exactly  in  the  condition  of  those  which  had  been  planted,  contained 
91.4  per  cent,  of  dry  matter,  and  left  by  incineration  3.14  per  cent. 
t^  residue.  The  five  peas  planted,  taken  as  dry  and  free  from  ashes, 
V  >uld  therefore  have  weighed  1.072  gram.,  or  16.54  grs.  troy. 

A-naiysis  showed  in  the 

Pea*  town.  Peat  collected.  Straw  and  rootfc 

Carbon 48.0  54.9  52.8 

Hydrogen 6.4  6.8  6.2 

Azote 4.3  3.6  1.6 

Oxygen 41.3  34.7  39.4 

100.0  100.0  100.0 


RESULTS. 

Carbon.  Hydrog^en.  Oxygen.  Axote. 

Seeds  16..549,  containing 7.950  1.065  6.523  0.710 

Crop   68.560,          "    *     3G.680  4.384  25.930  1.559 

52.02  grs.  by  cultivation +28.73  +3.319  +19.11  +0.849 

From  this  experiment  it  appears  that  16.549  grs.  of  seed  found  in 
the  air,  and  obtained  from  the  water  with  which  they  had  b*^en  sup- 
plied during  their  growth,  52.02  grs  of  elementary  matter  io  the 
course  of  riinety-nine  days'  growth,  during  the  warmest  months  of 
the  year ;  and  that  the  quantity  of  azote  originally  contained  in  th§ 
»eed  was  more  than  doubled  in  the  produce  arrived  at  inatprity. 

*  Peas 45.89 

Straw  and  shells 22.66 


"^otal  weight  of  the  crop 


46  EVOLUTION  AND  GROWTH. 

THIRD  EXPERIMENT. 

GROWTH   OF  WHEAT. 

Forty-six  wheat  corns  were  sown  in  burnt  sand  at  the  beginning 
of  the  month  of  August.  At  the  end  of  September,  the  stalks  were 
from  fourteen  to  fifteen  inches  in  height.  The  greater  number  of 
the  lower  leaves  were  yellow.  The  roots  were  of  very  considerable 
length,  and  formed  a  kind  of  mat,  which  made  it  difficult  to  wash 
and  free  them  from  sand. 

RESULTS  OF  THE  ANALYSIS. 

Seeds.  Crop. 

Carbon 46.6  48.2 

Hydrogen 5.8  5.8 

Azote 3.45  2.0 

Oxygen 44.15  44.0 

100.00  100.0 

RESULTS. 

Grs.                         Carbon.  Hydfo«^en.    Oxyg-en.    Aiofo 

The  seed  dried 25.38  containing  11.84  1.46        11.19       0.87 

The  seed  dried 46.65         "         22.47  2.67       20.57       0.92 

Gainbycultnre 21.27                 +10.63  +1.21      +9.38    +0.05 

In  the  course  of  three  months'  growth,  therefore,  the  weight  of 
the  seed  had,  so  to  speak,  doubled  ;  but  the  grain  azote  was  scarcely 
appreciable.  Nevertheless,  this  experiment  upon  the  wheat  had 
been  conducted  under  precisely  the  same  circumstances  as  that 
made  upon  the  clover.  The  two  crops  grew  in  the  same  apparatus  ; 
they  were  watered  with  the  same  water,  which  they  received  very 
nearly  in  the  same  quantity  ;  the  seed  was  even  sown  in  vessels 
having  exactly  the  same  extent  of  surface,  in  order  that  either  crop 
might  be  exposed  to  the  same  chances  of  error  arising  from  the  ac- 
cidental presence  of  dust  in  the  atmosphere. 

The  plants  produced  under  the  circumstances  indicated  T-ere  far 
from  presenting  the  vigor  which  they  would  have  shown  had  they 
been  grown  in  the  open  field.  After  three  months  of  growth,  the 
clover  was  much  less  forward  than  some  which  had  been  sown,  for 
comparison,  in  a  manured  and  gypsumed  soil  at  the  same  time.  The 
whea*  showed  the  same  weakness ;  and  after  the  second  month,  I 
observed  that  each  new  leaf  which  was  developed  upward  in  the 
stem,  caused  one  of  those  at  the  lower  part  to  droop  and  grow  yel- 
low. The  peas,  although  they  reached  maturity,  had  much  smaller 
leaves,  and  both  fewer  and  smaller  seeds  than  similar  plants  grown 
at  large. 

It  is  well  known  that  it  is  in  great  part  due  to  the  fertility  of  the 
soil  in  which  seeds  are  grown  that  the  health  and  vigor  of  young 
plants  must  be  ascribed.  A  celebrated  agriculturist,  Schwartz,  as- 
certained, for  example,  that  young  col^worts  or  cabbage  plants  ex- 
hausted in  a  remarkable  manner  the  soil  in  which  they  were  raised 
fpjr  transplantation.     The  good  efiects  of  the  first  nourishment  ob- 


ASSIMILATION    OF    ELEMENTS.  47 

tained  in  a  well-manured  soil  must  extend  subsequently  to  every 
part  of  the  vegetable  ;  and  it  is  easily  understood  that  a  plant  which 
has  languished  in  its  earliest  periods  of  existence  can  never  acquire 
a  good  constitution  afterwards. 

It  therefore  becamr  interesting  to  carry  out  experiments  of  the 
nature  of  those  already  related,  in  connection  with  plants  vigorously 
organized,  and  which  had  been  raised  in  the  first  instance  in  a  fer- 
tile soil. 

FOURTH  EXPERIMENT. 

GROWTH    OF   CLOVER. 

In  a  field  of  clover  sown  in  the  spring  of  the  preceding  year, 
several  plants  as  like  one  another  as  possible  were  chosen.  The 
earth  adhering  to  the  roots  was  removed  by  careful  washing  under 
a  small  stream  of  water ;  the  plants  were  then  made  dry  between 
leaves  of  blotting  paper,  and  exposed  for  a  few  hours  in  the  air. 
Three  of  these  plants  preserved  for  analysis  weighed  when  green 
5.750  grammes,  or  104.20  grs.  troy. 

Three  other  plants,  weighing  6.820  gram,  or  105.28  grs.  troy, 
were  set  in  sand  recently  calcined  and  moistened  with  distilled 
water.  The  transplanting  took  place  on  the  28th  of  May,  and  the 
plants  were  forthwith  protected  from  dust. 

For  some  days  they  seemed  to  languish,  but  by  and  by  they  be- 
came remarkably  vigorous.  In  a  month  the  clover  had  grown  to 
twice  its  original  height,  and  the  leaves  were  of  the  most  beautiful 
green  :  the  plants  had  in  all  respects  as  fine  an  appearance  as  the 
clover  of  the  same  age  which  had  been  left  growing  in  the  field. 
The  flowers  showed  themselves  upon  the  8th  of  July,  and  by  the 
15th  the  flowering  was  complete  :  an  end  was  put  to  the  experiment 
on  the  1st  of  August. 

RESULTS    OF   THE    ANALYSIS. 
BEFORE   CULTURE.  AFTER   CULTURE. 

Carbon 43.42  53.00 

Hydrogen 5.40  6.51 

Azote 3.75  2.45 

Oxygen ..47.43  38.14 

100.00  100.00 

RESULTS. 

Tlie  trefoil  transplanted,  weighed  when  dry  and  freed  from  ashes 13.64 

After  sixty-tiiree  days'  culture  on  iiarren  soil,  it  weighed 34.96 

Gained  during  culture 21.32 

Carbon.      Hydrogen.  Oxyg-en.        Azote 

The  plant  contained :  before  culture 5.92         0.74         6.4G         O.r>0 

afterculture 1?.52  2.23        13.32        0.SG4 

Difference.. +  12.60      +1.49      +6.86     +0.35 

Thus  in  two  months'  growth  at  the  cost  of  the  air  and  water,  the 
clover  had,  so  to  say,  tripled  its  quantity  of  organic  matter;  and  the 
weight  of  azote  contained  in  it  was  very  nearly  doubled. 


48  EVOLUTION    AND   GKOWTH.  - 

FIFTH  EXPERIMENT. 

VEGETATION  OF  OATS. 

I  always  failed  in  my  attempts  to  transfer  wheat  plants  from  the 
ordinary  soil  in  which  the  grain  had  been  sown  to  barren  sand  ;  they 
never  survived  the  transplantation.  It  was  not  different  with  oat 
plants ;  they  also  always  died.  It  was  at  first  supposed  that  the 
delicate  radicles  of  these  plants  had  been  injured  in  the  process  of 
taking  them  up  and  freeing  their  roots  from  adhering  vegetable  soil ; 
but  I  soon  saw  that  this  could  not  have  been  the  case,  for  the  same 
plants,  treated  precisely  in  the  same  manner,  took  very  promptly 
when  transplanted  to  garden  mould,  and  even  when  they  were  put 
with  their  roots  in  pure  water.  It  was  with  water,  therefore,  that 
the  following  experiment  was  conducted. 

June  20th,  several  oat  plants  were  taken  up  from  a  field,  and  their 
roots  were  washed  and  cleansed. 

Three  plants  preserved  for  analysis,  weighed  159.011  grs. 

Four  plants,  the  subjects  of  experiment,  weighed  221.844  grs. 
troy.  They  were  protected  from  dust,  their  roots  dipping  into  a 
vessel  containing  distilled  water,  which  was  regularly  kept  up  to 
the  same  level.  By  the  middle  of  July  the  stalks  of  these  plants 
had  grown  to  twice  their  former  length ;  and  at  this  time  it  would 
have  been  difficult  to  have  distinguished  them  from  those  growing 
in  the  open  field.  By  the  end  of  July  the  clusters  had  formed  ;  and 
on  the  10th  of  August  the  grain  seemed  ripe.  It  was,  therefore, 
taken  np  and  dried  in  the  stove,  and  reduced  to  powder  to  complete 
the  desiccation  at  110°  cent.  (230°  Fahr.) 

ANALYSIS    OF   THE   CROP. 

Transplanted.  Gathtred  from  the  Held. 

Carbon 53.0  48.0 

Hydrogen 6.8  6.2 

Oxygen 36.4  44.0 

Azote   3.8  1.7 

100.0  100.0 

SUMMARY. 

Carbon.  Ujrdre^a.  Oxjrgta.  Axott. 
The   oats   when  transplanted 

contained 12.967               1.636  8.770  0.910 

AAer  48  days  of  growth  in  dis- 
tilled water  they  contained •  •  23.157               2.979  21.180  0.818 

+10.190  +1.343  +12.410  —0.099 

The  analysis,  therefore,  indicates  a  trifling  loss  of  azote. 

In  recapitulating  the  conclusions  obtained  from  these  experiments, 
we  find : 

First.  That  trefoil  and  peas  grown  in  a  soil  absolutely  without 
manure,  acquired  a  very  appreciable  quantity  of  azote,  in  addition  to 
a  large  quantity  of  carbon,  hydrogen,  and  oxygen. 


ASSIMILATION   OF   ELEMENTS.  49 

Second.  That  wheat  and  oats  grown  in  the  same  circumstances, 
took  carbon,  hydrogen,  and  oxygen  from  the  air  and  water  around 
them ;  but  that  analysis  showed  no  increase  of  azote  in  these  plants 
after  their  maturity. 

The  mode  of  experimenting  followed  had  it  in  view  simply  to 
determine  the  assimilation  of  azote  by  certain  vegetables,  without 
entering  into  the  question  of  the  means  by  which  this  was  effected  ; 
and,  indeed,  in  reference  to  the  point,  I  can  only  offer  conjectures. 

Azote  may  enter  the  living  frame  of  plants  directly,  or,  as  M. 
Piobert  has  maintained,  in  the  state  of  solution  in  the  water,  always 
aerated,  which  is  taken  up  by  their  roots.*  The  observations  of 
vegetable  physiologists  are  nj)t  generaly  favorable  to  this  view.  It 
is  farther  possible  that  the  element  in  question  may  be  derived  from 
ammoniacal  vxpors,  which,  according  to  some  philosophers,  exist  in 
infinitely  small  proportion  in  our  atmosphere.  These  vapors,  dis- 
solved by  rains  and  dews,  would  readily  make  their  way  into  plants, 
and  might  there  undergo  elaboration. 

It  is  long  since  Saussure  alluded  to  the  probable  influence  of  am- 
moniacal vapors  upon  vegetation.  Prof.  Liebig  has  more  recently 
maintained  the  same  opinion,  and  has  taken  particular  pains  to  prove 
that  rain-water  always  contains  a  very  minute  quantity  of  carbonate 
of  ammonia. 

To  this  cause,  which  must  have  the  effect  of  infusing  an  azotized 
principle  into  the  tissues  of  plants,  must  be  added  another,  which  is 
perhaps  not  thp  least  energetic.  It  is  this,  that  under  certain  elec- 
trical influences,  of  which  M.  Becquerel  has  made  a  particular  study, 
hydrogen  in  the  nascent  state,  in  contact  with  azote,  may  actually 
give  rise  to  ammonia.  By  means  of  this  view,  it  becomes  easy  to 
conceive  how  non-azotized  organic  substances,  under  the  mere  in- 
fluence of  the  putrid  fermentation,  might  give  origin  to  ammoniacal 
salts,  which  would  then  exercise  a  fertilizing  action  on  the  soil. 

During  the  growth  of  plants,  a  portion  of  the  water  absorbed  by 
the  roots  is  evidently  assimilated ;  and  this  circumstance  enables  us 
to  conceive  the  formation  of  many  of  the  immediate  principles  of 
vegetables,  the  chemical  composition  of  which  is  precisely  repre- 
sented by  carbon  and  the  elements  of  water ;  such  as  starch,  sugar, 
etc.  We  can  also  understand  the  presence  of  those  principles, 
which  have  further  a  certain  proportion  of  oxygen  in  excess,  inas- 
much as  we  have  ascertained  that  during  the  decomposition  of  car- 
bonic acid  by  the  green  parts  of  vegetables,  the  whole  of  the  oxygen 
is  not  eliminated.  But  there  are  substances  elaborated  by  plants 
which,  with  reference  to  oxygen,  contain  a  quantity  of  hydrogen 
much  greater  than  is  requisite  to  form  water ;  such  are  the  resins 
and  other  carburets  of  hydrogen  in  the  cone-bearing  trees,  and  the 
fat  oils  in  the  oleaginous  seeds.  This  excess  of  hydrogen  led  severai 
physiologists  to  conclude  that  water  was  decomposed  in  the  course 
of  vegetation, — that  there  was  fixation  of  its  hydrogen  and  disen- 
gagement  of  its  oxygen  gas. 

•  Piobert,  M6m.  de  rAcad6mle  de  Metz,  1837,  -  - — 'i 

■5  ^M^ 


69  EVOLTTTION   AND    GROWTH. 

Nevertheless,  the  presence  of  hydrogen  in  excess  in  certain  im- 
mediate vegetable  principles  is  no  decisive  proof  of  the  disjunction 
of  the  elements  of  water ;  and  if  no  definitive  conclusion  lias  been 
come  to  on  the  point,  up  to  the  present  moment,  it  is  because  these 
hydrogenized  principles  are  produced  in  plants  which  live  under  the 
influence  of  certain  organic  substances  that  are  met  with  in  the  soil, 
where  they  act  as  manures,  their  composition  being  always  complex, 
and  often  highly  hydrogenized. 

The  experiments  of  M.  de  Saussure  do  not  lead  us  to  suspect 
the  decomposition  of  water ;  inasmuch  as  by  keeping  plants  for  a 
whole  month,  under  receivers  filled  with  atmospheric  air  freed  from 
carbonic  acid,  no  apparent  evolution  of  oxygen  was  observed. 
Operating  in  the  same  manner  with  air  containing  a  certain  propor- 
tion of  carbonic  acid,  the  quantity  of  oxygen  disengaged  was  always 
less  than  that  which  entered  into  the  constitution  of  the  acid  de- 
composed. 

This  is  the  place  to  observe,  and  in  connection  with  these  very 
experiments  of  M.  de  Saussure,  how  little  satisfactory  this  partial 
decomposition  of  carbonic  acid,  which  corresponds  to  no  definite 
proportion,  appears.  We  already  feel  the  difficulty  of  conceiving 
that  this  acid  should  be  completely  reduced  by  a  living  plant ;  that 
is  to  say,  that  the  whole  of  its  carbon  should  become  assimilated. 
The  entire  separation  of  a  body  so  greedy  of  oxygen  as  carbon  from 
its  most  highly  oxygenated  compound,  must  needs  excite  the  greatest 
astonishment. 

The  readiest  conception  suggested  by  the  facts  is  this ;  that  by 
the  agency  of  the  solar  light,  and  under  the  influence  of  the  green 
matter,  carbonic  acid  is  turned  into  carbonic  oxide  by  losing  a  por- 
tion of  its  oxygen.  This  modification  appears  more  in  conformity 
with  the  ascertained  principles  of  chemical  and  physiological 
science.  Still  it  must  be  allowed,  that  facts  agree  as  little  with 
this  mode  of  viewing  the  question  as  with  that  which  assumes  the 
entire  decomposition  of  the  carbonic  acid.  On  the  first  assumption, 
the  proportion  of  oxygen  set  at  liberty  is  too  small ;  in  the  second, 
it  is  too  great. 

The  negative  results  of  M.  de  Saussure,  in  relation  to  the  separa- 
tion of  the  elements  of  water  during  vegetation,  were  obtained  in 
the  absence  of  carbonic  acid,  whilst  the  experiments  which  estab- 
lished the  decomposition  of  this  latter  body,  were  necessarily  made 
under  the  influence  of  moisture.  It  is  possible,  therefore,  that  the 
water  and  the  carbonic  acid  underwent  simultaneous  decomposition  ; 
and  it  becomes  interesting,  taking  this  view,  to  inquire  whether  the 
hypothesis  according  to  which  carbonic  acid  undergoes  transforma- 
tion into  carbonic  oxide  does  not  acquire  a  certain  degree  of  proba- 
bility by  calling  in  the  effect  of  the  decomposition  of  water  in  the 
phenomena  observed. 

One  volume  of  the  gaseous  oxide  of  carbon  takes  half  a  volume 
of  oxygen  gas  to  form  one  volume  of  carbonic  acid.  Reciprocally, 
©ne  volume  of  carbonic  acid  gas,  in  undergoing  transformation  inta 


ASSIMILATION    OF    ELEMENTS.  51 

the  oxide  of  carbon,  will  give  one  volume  of  the  oxide,  -f  |  a  volume 
of  oxygen  gas. 

Thus,  in  the  hypothesis  which  we  now  discuss,  for  each  volume 
of  carbonic  acid  that  is  modified  by  the  vegetation,  there  will  he  half 
a  volume  of  oxygen  gas  disengaged.  Any  oxygen  more  th.-».n  tbi<i 
half  volume  which  appears,  must  he  regarded  as  proceeding  froi'* 
the  decomposition  of  water,  the  hydrogen  of  which  will  have  beev 
assimilated  by  the  plant  at  the  same  time  as  the  carbonic  oxido  de- 
rived from  the  carbonic  acid  ;  and  this  view  would  perhaps  enabh 
us  to  conceive  how  the  volume  of  oxygen  which  is  disengaged  du- 
ring the  process  of  vegetation,  may  exceed  the  volume  which  ought 
to  be  produced,  if  the  carbonic  acid  decomposed  really  passed  into 
the  state  of  carbonic  oxide. 

We  may  perchance  obtain  a  more  convincing  proof  of  the  separa- 
tion of  the  elements  of  water,  in  analyzing  plants  grown  in  a  soil 
absolutely  without  any  organic  matter  capable  of  aflfording  them  hy- 
drogenous elements. 

In  fact,  if  a  plant,  which  is  grown  under  such  circumstances,  con- 
tains hydrogen  in  any  larger  proportion  than  that  which  were  neces- 
sary to  transform  its  oxygen  into  water,  we  might  conclude,  with 
some  certainty,  that  the  elements  of  water  had  been  separated  ;  the 
objection  made  on  the  score  of  the  presence  of  manure  would  then 
be  got  rid  of  entirely.  The  analyses  which  have  already  been  laid 
before  the  reader  supply  data  for  this  investigation  ;  it  has  only  to 
be  ascertained  whether,  in  the  elements  gained  in  the  course  of 
vegetation,  the  hydrogen  is  in  excess  with  reference  to  the  oxygen 
or  not.  The  following  table  presents  a  summary  view  of  our  ex- 
periments : 

Oxyfren  Hydrogfen  Hydrogen  Hydrogen 

assimilated.  as«imilaied.  forming  water,  in  excess. 

Experiment  1.    Trefoil 18.926           2.717  2.362  0.355 

Experiment  2.    Peas 19.096           3.319  2.392  0.926 

Experiments.    Wheat 9.386            1.204  1.173  0.030 

Experiment  4.    Transplanted  Trefoil  . .  6.854            1.495  0.849  0.646 

Experiment  5.    Oats 12.410           1.343  1.343 

In  the  four  first  experiments,  the  hydrogen  gained  evidently  ex- 
ceeds very  sensibly  the  quantity  required  by  the  oxygen  to  form 
water.  The  experiment  with  the  oats,  indeed,  presents  an  excep- 
tion ;  but  it  must  be  remembered  that  here  a  loss  of  azote  was  ascer- 
tained. These  analyses,  therefore,  appear  to  indicate  an  assimilation 
of  hydrogen  in  the  course  of  vegetation,  in  consequence  of  a  decom- 
position of  water  analogous  to  that  of  carbonic  acid,  and  very  proba- 
bly effected  by  the  same  means. 


52  INORGANIC   CONSTITUENTS. 


§  III.— OF  THE  INORGANIC  MATTERS  CONTAINED  IN 
PLANTS— THEIR  ORIGIN— OF  THE  CHEMICAL 
NATURE  OF  SAP. 

When  a  plant  is  burned,  there  always  remains  a  residue,  which  is 
commonly  designated  as  the  ash.  Every  part  of  a  plant  gives  a 
residue  of  the  same  essential  kind ;  but  it  varies  in  its  quantity 
and  somewhat  also  in  its  composition.  Equal  weights  of  dry 
herbaceous  plants  leave  more  ashes  than  woody  plants.*  In  a 
tree,  the  trunk  gives  more  ash  than  the  branches,  and  these  give 
less  than  the  leaves. f  The  residue  left  by  the  combustion  is  com- 
monly composed  of  salts — alkaline  chlorides,  with  bases  of  potash 
and  soda,  earthy  and  metallic  phosphates,  caustic  or  carbonated  lime 
and  magnesia,  silica,  and  oxides  of  iron  and  of  manganese.  Seve- 
ral other  substances  are  also  met  with  there,  but  in  quantities  so 
small  that  they  may  be  neglected. 

The  principles  usually  met  with  in  the  ashes  of  vegetables  are 
always  found  in  the  soil  which  exercises  the  greatest  influence  upon 
the  nature  and  quantity  of  the  saline  and  earthy  matters  which  re- 
main after  the  combustion  of  plants.  Those  which  grow  in  a  soil 
derived  from  silicious  rocks,  yield  ashes  that  are  richer  in  silica  than 
those  that  are  produced  in  a  calcareous  soil.  But,  according  to  M. 
de  Saussure,  the  quality  of  the  manure  has  a  still  more  decided  in- 
fluence on  the  nature  of  the  ash  than  the  geological  constitution  of 
the  soil ;  according  to  this  observer,  plants  of  the  same  species, 
which  have  grown  upon  a  calcareous  sand,  and  upon  a  granitic  sand, 
contain  the  same  kind  of  ashes,  if  they  have  been  manured  with  the 
same  dung  ;  and  different  species,  although  growing  in  the  same 
earth,  do  not  contain  the  saline  and  earthy  constituents  of  their 
ashes  in  the  same  proportions.! 

♦  Kirwan,  Memoirs  of  the  Royal  Irish  Academy,  voL  T. 
t  Pertuis,  Annales  de  Chiraie,  l^e  s6rie,  t.  xix. 
i  Saussure,  Sechercbes  chimiques,  p.  283. 


ASHSS. 


58 


QUANTITY    or   ASHES   CONTAINED    IN   THE    DIFFERENT   PARTS    OF 
VEGETABLES,    ACCORDING    TO    M.    DE    SAUSSURE.* 


NAMK    OK   THB    PLANT. 

Times  when  taken 
for  analysis. 

Ashes. 

Oak  leaves 

10  May 

0,053 

Ditto    do.        .         .         . 

27  September 

0,055 

1     Oak  branches  barked 

10  May 

0,004 

Bark  of  tliese  branches  . 

. 

0,060 

Oak  wood  distinct  from  alburnum  . 

0,002 

Alburnum  from  same  wood      . 

0,004 

Bark  of  same  tree  .... 

. 

0,000 

Liber  of  the  preceding  bark     . 

... 

0,073 

Leaves  of  poplar     .... 

May 

0,066 

Ditto           ditto       .... 

September 

0,093 

Trunk  of  ditto       .... 

... 

0,008 

Bark  of  trunk  of  ditto     . 

, 

0,072 

Spanish  mulberry-tree  wood    .        • 

, 

0,007 

Alburnum  of  mulberry    . 

, 

0,013 

Bark  of  ditto 

, 

0,089 

Liber  of  ditto           .... 

, 

0,088 

Chestnut-tree  leaves        .         .        , 

10  May 

0,072 

Ditto         ditto          .... 

23  July 

0,084 

Flowers  of  chestnut-tree 

10  May 

0,071 

Ripe  chestnuts         .... 

5  October 

0,034 

Peas  flowering        .... 

.                  , 

0,095 

Peas  in  pod 

. 

0,081 

Beans  in  flower       .... 

0,122 

Ditto    in  pod  ... 

0,066 

Bean  straw 

0,115 

Beans      

0,033 

Jerusalem  artichoke  in  flower 

0,137 

Ditto               in  seed    .        . 

0,093 

Wheat  straw  .                 ... 

0,043 

Wheat    ... 

0,013 

Bran 

0,052 

Indian  corn  straw    .... 

0,084 

Indian  corn     .                           . 

0,010 

Barlev  straw  .         .                 .         . 

0,042 

Barley 

0,018 

Oats 

0,031 

Pine-tree  leaves  (Jura)    . 

20  June 

0,029 

Ditto         ditto     (Brocken)      . 

20  June 

0,029 

Pine-tree  branches  without  leaves    . 

20  June 

0,015 

All  these  estimates  of  ashes  refer  to  plants  dried  during  sevei  tl 
weeks  in  a  stove  heated  to  25°  cent.  {IT  Fahr.)  By  such  drying, 
however,  vegetable  substances  are  very  far  from  losing  the  whole 


Saussure,  Recherches  chimiquos,  p.  233, 
5* 


54 


INORGANIC   CONSTITUENTS. 


of  the  water  which  they  contain.  The  quantities  of  ashes,  there- 
fore, mentioned  by  M.  de  Saussure,  if  they  be  referred  to  vegetables 
absolutely  dry,  are  somewhat  too  small. 

I  present  a  few  estimates  of  ashes  from  analyses  which  I  have  had 
occasion  to  make  of  some  of  those  plants  which  are  the  usual  sub- 
jects of  cultivation  with  us.  The  drying  here  was  always  performed 
with  care  in  an  oil-bath  heated  to  110"  cent.  (230°  Fahr.)* 


Substance  dried  at  S30"  Fahr.  Ashec. 

Wheat  Straw 0,070 

Wheat 0.024 

Rye  straw 0,036 

Rye 0,023 

Oat  straw 0.051 

Oats 0.040 

Potatoes 0,040 

Beet-root 0,063 


Substance  dried  at  830'  Fahr.  Ashes. 

Turnip 0,076 

Jerusalem  artichoke 0,060 

Stems  of  ditto 0,028 

White  peas 0,031 

Pea  straw 0,113 

Clover  hay 0,077 

^Meadow  hay 0,090 

'  After  grass  (meadow) 0,100 


We  owe  to  M.  Berthierf  the  following  results  of  the  incineration 
of  different  kinds  of  wood  burned  in  the  state  in  which  they  are  gen- 
erally used. 


Kinu  of  wood.  Ashes. 

Fir 0,0083 

Birch 0,0100 

False  ebony 0,0125 

Hazel 0.0157 

White  mulberry. 0.0160 

Saint  Lucia  wood 0,0160 

Elder 0.0164 

Judea-trec 0,0170 

Oak  (branches) 0.0250 

Oak  bsirk 0,0600 

Lime-tree 0,0500 


Kind  of  wood.  Ashes. 

Poplar  bark 0,0020 

Box  wood  0,0036 

Oak  barked,  ash,  pine,  birch,  &c.  0.0040 

Thorn 0,0050 

Aspintree 0,0060 

Oakbark 0,0120 

Black  wood 0,0149 

Mahogany 0,0160 

Ebony O.O'fiO 

Oak  (fagot) 0.0220 

Fearns 0,0450 


We  possess  several  analyses  of  ashes  from  different  parts  of  the 
same  plants  in  the  researches  of  MM.  de  Saussure  and  Berthier. 
As  the  knowledge  of  these  saline  substances  may  prove  highly  im- 
portant m  our  agricultural  applications,  and  as  it  further  completes, 
in  some  sort  the  facts  that  bear  ujwn  the  chemical  phenomena  of 
vegetation,  1  here  add  a  table  of  the  results  obtained  by  the  skilful 
analys's  just  quoted : 

♦  Ann.  de  Chimie,  t.  i.  page  234.  3e.  s6rie. 
T  Traits  des  Essais,  t  i,  page  259 


ASHES. 


55 


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Chestnuts 

Menyanthes  trifoliata  in  flower 

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The  same  cleared  of  seed 
Beans           .... 
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Indian  corn  straw 
Indian  corn 
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66 


INORGANIC   CONSTITUENTS. 


In  his  researches  upon  the  same  subject,  M.  Berthier  determineJ 
the  relation  of  the  insoluble  to  the  soluble  matters  in  each  species 
of  ash  examined ;  and  the  two  kinds  of  salts  were  then  analyzed 
separately. 


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Oak  bark 

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Hazel 

Chinese  mulberry 

White  mulberry 

Oitto     ditto      . 

Orange  or  lance-w* 

White  oak 

Birch 

False  ebony      . 

Fir  .        /      . 

Wheat  straw  . 

Potato  stems    . 

ASHES. 


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58 


INORGANIC    CONSTITUENTS. 


COMPOSITION    OF    THE    ASHES    OF    SEVERAL    PLANTS    ANALYZED 
BY    M.    BERTHIER. 


Fern. 

Wheal 
straw. 

Horse-tail 
grass. 

Heath. 

Tansy. 

Observations. 

Sulphate  of  potash- .  • 
Chloride  of  potassium 
Carbonate  of  potash.  • 

Silicate  of  potash 

Silica^ 

0,007 

0,730 
0,248 

0,010 
0,005 

0,004 
0,032 

0,130 
0,715 
0,096 

0,083 

0,120 
0,114 

0,505 
0,062 
0.144 
0,022 
0,030 

0,050 
0,012 
0,068 

0,375 
0,280 

0,130 
0,010 
0,014 
0,061 

0,033 
0,090 
0,167 

0,i65 
0,434 

o.]'oo 

0,002 
0.007 
0.002 

The        wheat 
straw  was   from 
a   strong  calca- 
reous 80ll. 

The  tansy  wa« 
from  a  sandy  gar- 
den soil. 

Carbonate  of  lime 

Sulphate  of  lime 

Phosphate  of  lime  . . . 

Oxide  of  iron 

1  Oxide  of  manganese.. 

A  remark  made  by  Berthier,  and  arising  out  of  the  preceding 
analyses,  is  the  absence  of  alumina  in  the  constituent  principles  of 
the  ashes  examined.  The  results  previously  obtained  by  M.  de 
Saussure  fully  confirm  this  remark ;  and  if  in  some  cases  traces  of 
alumina  were  detected,  the  circumstance  was  attributed  to  the  clay 
which  might  accidentally  have  adhered  to  the  plants.  According  to 
M.  Berthier  the  absence  of  alumina  is  probably  owing  to  its  insolu- 
bility in  water,  and  its  weak  affinity  for  the  organic  acids.  The  solu- 
ble salts  of  alumina  with  mineral  acids  are,  it  is  well  known,  unfa- 
vorable to  vegetation,  and  in  an  arable  soil  they  could  not  exist  along 
with  calcareous  or  alkaline  carbonates  :  they  would  be  immediately 
decomposed. 

However,  alumina  appears  actually  to  have  been  observed  in  the 
state  of  salt  in  the  juices  of  certain  plants :  li/copodium  arniplanatum^ 
an  infusion  of  which  is  employed  as  a  mordant  in  dyeing,  contains 
tartrate  of  alumina  ;*  the  same  salt  has  been  detected  in  verjuice  ;  and 
as  we  shall  see  presently,  Vauquelin  found  acetate  of  alumina  in  the 
sap  of  the  birch-tree.  1  may  add,  that  in  a  considerable  numb({r  of 
analyses  of  ashes,  produced  from  plants  and  seeds  of  my  own  grow- 
ing, I  always  obtained  traces  of  alumina  :  but  I  would  not  venture 
to  affirm  that  the  earth  here  was  not  accidental. 

Silica  is  met  with  in  only  very  small  quantity  in  the  ashes  of  wood. 
It  is  found,  on  the  contrary,  in  considerable  proportion  in  the  ashes 
of  several  annual  and  biennial  plants,  and  more  especially  in  those 
of  the  cereals.  Sir  Humphrey  Davy  found  silica  in  the  epidermis 
of  the  Indian  rush. 

If  we  compare  the  ashes  of  the  same  species  of  wood  grown  in 
soils  of  different  kinds,  we  see,  says  M.  Berthier,  that  they  may  dif- 
fer very  perceptibly ;  which  seems  to  establish  the  fact  that  the  soil 
exercises  a  certain  degree  of  influence  on  their  constitution.  Thus 
oak-wood  from  Roque  des  Arcs,  grown  in  a  decidedly  calcareous 
soil,  yielded  ashes  almost  entirely  ODnsisting  of  carbonate  of  lime, 


Berzelios,  TraiU  de  Chimin,  t.    r.  p.  130,  French  translation. 


ABSORPTION  OF  SALTS.  59 

while  those  left  by  an  oak  from  the  department  of  la  Somme,  contain- 
ed much  magnesia  and  phosphate  of  lime,*  Tlie  ashes  from  a  white 
mulberry  of  Nemours  contained  mOre  than  0.10  of  phosphoric  acid, 
while  scarcely  any  traces  of  it  were  ftmnd  in  those  of  a  similar  mul- 
berry from  the  calcareous  soil  of  Provence.  The  most  remarkable 
inference  deducible  from  the  analyses  of  M.  Berlhier,  is  that  which 
is  connected  with  the  composition  of  the  ashes  yielded  by  trees 
growing  in  the  same  soil.  It  is  observed  that,  for  analogous  species, 
the  ashes  also  bear  the  closest  analogy ;  and  on  the  contrary,  it  is 
found  that  trees  of  very  distinct  genera  yield  ashes  of  quite  a  dif- 
ferent quality  ;  results  which  lead  to  this  important  conclusion,  that 
plants  possess  the  faculty  of  selecting  in  the  soil  the  substances 
which  are  best  suited  to  their  special  organizations.  This  is  a  point 
which  we  shall  have  an  opportunity  of  discussing,  when  we  come 
to  treat  of  rotations  of  crops. 

The  substances  composing  the  ashes  of  vegetables,  are  not  all  in 
the  state  in  which  they  existed  in  the  vegetable  tissue.  In  plants 
there  constantly  exist  organic  acids,  which,  in  general,  are  combined 
with  mineral  bases.  During  the  incineration  of  plants  these  organic 
acids  are  destroyed,  and  the  result  of  their  destruction  is  an  alkaline 
carbonate,  if  the  pre-existing  acid  was  united  with  soda  or  potash  ; 
a  calcareous  vegetable  salt,  again,  yields  carbonate  of  lime  ;  and  a 
magnesian  salt  gives  magnesia,  from  the  well-known  inability  of  this 
earth  to  retain  carbonic  acid  at  a  high  temperature.  Thus,  the 
greater  part  of  the  carbonates  which  enter  into  the  composition  of 
vegetable  ashes,  are  formed  by  the  mere  fact  of  incineration.  The 
Baits  which  resist  the  action  of  a  strong  heat,  as  the  phosphates,  sul- 
phates, and  chlorides,  are  the  only  ones  which  in  the  ashes  retain 
the  state  in  which  they  existed  in  the  living  plant. 

Water  being  the  vehicle  which  must  convey  the  mineral  salts  from 
the  soil  into  the  vegetable,  we  do  not  always  perceive  how  they  can 
penetrate.  To  explain  the  presence  in  plants  of  a  salt  so  insoluble 
as  the  neutral  phosphate  of  lime,  M.  de  Saussure  admits,  from  satis- 
factory  experiments,  that  vegetable  juices  contain  the  double  phos- 
phate of  potash  and  lime,  and  of  potash  and  magnesia.f  Besides, 
several  bodies  considered  in  chemistry  as  insoluble,  are  not  so  abso- 
lutely. Silica  seems  to  possess  a  certain  degree  of  solubility, — at 
least,  M.  Payen  has  met  with  it  in  considerable  quantity  in  the  wa- 
ter of  the  Artesian  well  of  Crenelle,  and  in  the  water  of  the  Seine. 
We  know,  moreover,  that  several  insoluble  earthy  salts  are  dissolv- 
ed in  virtue  of  the  carbonic  acid  always  contained  in  the  waters 
with  which  the  soil  is  soaked.  Lastly,  it  is  not  improbable  that 
certain  insoluble  salts  have  their  origin  in  the  plant  itself,  engender- 
ed there  by  the  successive  arrival  and  reciprocal  action  of  soluble 
Baits. 

It  now  remains  for  us  to  examine  by  what  means  saline  substances 
are  introduced  into  the  tissues  of  vegetables,  and  within  what  limits 

*  These  ashes  were  from  the  carbon  of  the  oak ;  the  insoluble  part  gave  0.14  ol 
phosphate  of  lime,  and  0.08  of  magnesia. 
t  Saussiue,  Recherches  chimiques,  &c.  p.  321. 


60  INORGANIC    CONSTITUENTS. 

the  water,  which  is  essential  to  living  plants,  may  be  charged  with 
them  ;  for  it  is  within  what  may  be  called  common  experience,  that 
saline  solutions  of  certain  degrees  of  concentration,  oftentimes  act 
injuriously  on  vegetation. 

The  spongioles  which  terminate  roots  have  too  close  a  tissue  to 
allow  any  thing  but  fluids  to  pass  through  them.  All  attempts  to 
make  them  absorb  solid  bodies  in  a  stale  of  minute  division,  and  held 
in  suspension  in  water,  have  been  ineffectual.  In  these  attempts  the 
spongioles  have  acted  precisely  like  perfect  filters,  with  which  those 
that  we  employ  in  our  laboratories  cannot  be  compared.  Further, 
the  weakest  solutions  are  not  entirely  absorbed  by  certain  roots  ;  a 
kind  of  separation  takes  place  ;  a  portion  of  the  dissolved  salt  ap- 
pears to  abandon  the  water  at  the  moment  of  its  penetrating  the 
spongiole.  This  follows  from  the  researches  of  M.  de  Saussure, 
instituted  with  a  view  to  ascertain,  1st.  If  plants  absorb  substances 
dissolved  in  water  in  the  same  proportion  as  they  absorb  water  ;* 
2dl.y.  If  plants  make  a  selection  among  diflferent  substances  held  in 
solution  in  the  same  liquid. t 

In  solutions  severally  containing  eight  ten-thousandths  (0.0008) 
of  each  of  the  following  substances — chloride  of  potassium,  chloride 
of  sodium,  nitrate  of  lime,  sulphate  of  soda,  hydrochlorate  of  ammo- 
nia, acetate  of  lime,  sulphate  of  copper,  sugar-candy,  gum  arabic, 
and  extract  of  humus,J — several  entire  plants  with  their  roots,  of 
the  polygonum  persicaria^  (lakeweed  or  redshanks,)  which  had  lived 
for  some  time  in  distilled  water,  until  their  roots  had  commenced 
growing,  were  immersed. 

The  plants  lived  in  the  shade  during  five  weeks,  throwing  out  roots 
in  one  of  the  solutions  mentioned.  They  languished,  without  show- 
ing any  appearance  of  growth  in  the  solution  of  hydrochlorate  of 
ammonia,  and  could  only  be  kept  alive  in  the  sugared  water,  which 
soon  became  changed,  by  renewing  it  frequently.  They  died  at  the 
end  of  from  eight  to  ten  days,  in  gum  water,  and  in  the  solution  of 
acetate  of  lime.  They  held  out  but  for  two  or  three  days  in  the 
water  which  contained  sulphate  of  copper. 

Observations  precisely  similar  made  on  the  bidens  cannabina  pre- 
sented the  same  results,  with  the  sole  difference,  that  this  plant  lived 
for  much  shorter  times  than  the  redshanks. 

To  estimate  in  what  proportion  the  substances  dissolved  were  ab- 
sorbed, relatively  to  the  water,  M.  de  Saussure  made  use  of  the 
solutions  previously  employed  ;  but  he  brought  the  experiment  to  a 
close  when  the  plants  had  taken  up  precisely  half  the  liquid  which 
was  feeding  them.  Each  solution  fed  a  suflfieient  number  of  plants 
to  allow  of  this  condition  being  fulfilled  in  two  days.  Half  of  the 
liquid  remaining  after  each  experiment  was  analyzed,  and  the  quan- 
tity of  salt  found  therein,  showed,  by  the  difference  between  this 
and  the  quantity  originally  contained,  the  amount  which  had  pene- 
trated the  vegetable.     Representing  by  one  hundred  parts  the  whole 

*  Siuspure,  Rocherches  chimiques,  &.c.  p.  247.  t  Ihid.  rage  253. 

i  This  entered  into  the  solutions  only  in  the  proportion  of  t\\  o  ten-thousai^dtht 
0.0002.) 


ABSORPTION    OF    SALTS.  61 

of  the  substance  originally  dissolved,  it  is  evident  that  fifty  of  those 
parts  must  enter  the  plant,  if  the  absorption  of  the  saline  substances 
be  in  proportion  to  that  of  the  solvent.  But  the  experiment  proved, 
that  in  taking  up  half  the  volume  of  the  liquid,  the  polygonum  had 
absorbed  but — 

15  parts  of  chloride  of  potassium, 


13 

(( 

chloride  of  sodium, 

4 

t( 

nitrate  of  lime, 

14 

i( 

sulphate  of  soda, 

12 

(( 

hydrochlorate  of  ammonia, 

8 

u 

acetate  of  lime, 

29 

(( 

sugar, 

9 

(( 

gum. 

5 

(( 

extract  of  humus, 

47 

(( 

sulphate  of  copper. 

Under  the  same 

circumstances  the  bident  took — 

16  parts 

of  chloride  of  potassium, 

15 

(( 

chloride  of  sodium, 

8 

« 

nitrate  of  lime. 

10 

(( 

sulphate  of  soda. 

17 

(( 

hydrochlorate  of  ammonia, 

8 

{( 

acetate  of  lime. 

32 

(( 

sugar. 

8 

(( 

gum. 

6 

(( 

extract  of  humus. 

48 

(( 

sulphate  of  copper. 

It  follows  from  these  experiments  that  the  plants  absorbed  some 
part  of  the  different  substances  presented  to  them  ;  but  without  ex- 
ception, they  took  up  the  water  in  greater  proportion  than  the  mat- 
ters dissolved. 

On  multiplying  and  varying  these  experiments,  M.  de  Saussure 
always  arrived  at  the  same  general  results.  The  plants  uniformly 
took  up  more  of  the  alkaline  than  of  the  calcareous  salts,  and  more 
sugar  than  gum,  though  the  quantities  of  the  different  substances 
absorbed  varied  considerably. 

The  sulphate  of  copper  presented,  in  the  course  of  these  re- 
searches, an  anomaly  which  is  readily  explained.  We  see  that  this 
salt,  evidently  injurious  to  vegetation,  was  taken  up  in  a  large  dose. 
This  arises  from  its  corrosive  action  on  the  roots  :  sulphate  of  cop- 
per disorganizes  the  spongioles ;  and  these  organs  once  destroyed, 
absorption  takes  place  with  more  rapidity  and  in  greater  abundance. 
A  root  deprived  of  spongioles  is  in  the  condition  of  a  stalk,  or 
branch,  the  fresh  section  of  which  is  immersed  in  a  liquid.  Obser- 
vation proves,  in  fact,  that  substances  in  a  state  of  solution,  which 
by  reason  of  their  viscidity  are  incapable  of  making  their  way  into 
a  healthy  root,  are,  on  the  contrary,  readily  taken  up  by  a  cut  .stalk 
or  branch,  in  quantity  sufficient  to  dye  it  deeply,  if  it  was  a  coloring 
matter  that  was  presented  for  absorption. 

a 


62 


INORGANIC    CONSTITUENTS. 


In  the  preceding  experiments,  the  solution  contained  only  a  single 
substance.  In  those  which  follow,  M.  de  Saussure  dissolved  in  the 
water  two  or  three  salts,  a  mixture  of  sugar  and  gum,  &c.,  in  order 
to  ascertain  whether  the  plants  would  make  any  selection  from  mixed 
solutions. 

In  25  fluid  ounces  of  water  two  or  three  species  of  salt  were  dis- 
solved, the  weight  of  each  species  being  nearly  10  grains  troy. 
Each  ounce  of  water  would  therefore  contain  either  iths  or  '^ths  of 
a  grain  of  saline  or  soluble  matter.  As  in  the  preceding  experi- 
ments, the  plants  were  made  to  absorb  precisely  one  half  of  the  so- 
lutions. Analysis  pointed  out  the  quantity  and  the  nature  of  the 
substances  which  remained  in  the  liquid  not  absorbed,  and  conse- 
quently the  salts  which  had  penetrated  the  vegetable. 

In  reducing  this  table,  which  exhibits  the  results  obtained,  the 
weight  of  each  particular  salt  in  the  solution  is  represented  by  lOO 
parts. 


Substances  in  the  solution 
with  which  the  experiment  was  made. 

Weight  of  the  several  sub- 
stances  ti'-eu    up   by    the 
Polygcnun      in      imbibing 
one  half  of  the  solution. 

Weight  of  the  several  sub- 
stances taken   up  by   the 
Bident    in    imbibing    one 
half  the  solution. 

100  parts  1,7  weight. 

Sulphate  of  soda  efflores-ed  . 
Chloride  of  sodium 

12 

22 

7 
20 

Sulphate  of  soda  effloresced  . 
Chloride  of  potassium    . 

12 
17 

10 
17 

Acetate  of  lime 
Chloride  oi  potassium 

8 
33 

5 
16 

Nitrate  of  lime 
Hydrochlorate  of  ammonia    . 

4 
16 

2 
15 

Acetate  of  lime      . 
Sulphate  of  copper 

31 
34 

35 
39 

Nitrate  of  lime 
Sulphate  of  copper 

17 
34 

9 
56 

Sulphate  of  soda    . 
Chloride  of  sodium 
Acetate  of  lime 

6 

10 

traces 

13 

16 

traces 

Gum 

Sugar 

26 
34 

21 
46 

M.  de  Saussure  confirmed  these  results  in  experimenting  on  the 
common  peppermint,  {mentha  piperita,)  Scotch  pine,  and  common 
luniper.  The  substances  absorbed  in  greatest  proportion  by  the 
polygonum  and  bident  were  also  those  that  were  taken  up  in  largest 
quantities  by  these  plants. 


ABSORPTION    OF    SALTS.  63 

The  section  of  the  roots,  even  their  destruction,  favors,  as  we 
^ave  already  said,  the  introduction  of  the  matters  dissolved.  Plants 
whose  roots  had  been  removed,  no  longer  selected  the  substances 
dissolvsd  in  so  striking  a  manner  as  they  did  previously  ;  after  muti- 
latiort  they  absorbed  them  almost  indifferently,  in  larger  doses,  and 
perceptibly  in  the  same  proportion  as  the  water  which  held  them 
in  solution. 

Roots  with  their  spongioles  entire,  therefore,  suffer  one  substance 
in  solution  to  penetrate  the  plant  in  preference  to  another.  The 
chlorides  of  potassium  and  of  sodium,  for  instance,  find  entrance 
more  readily  than  the  acetate  and  nitrate  of  lime  :  sugar  more  readily 
than  gum  ;  and  precisely  as  when  isolated,  are  these  substances, 
when  combined,  absorbed  in  much  less  proportion  than  the  menstruum 
or  water  of  solution. 

M.  de  Saussure  is  not  disposed  to  admit  that  the  preference  which 
plants  evince  for  certain  salts,  for  certain  dissolved  substances,  results 
from  any  particular  faculty,  from  any  special  affinity.  He  rather 
inclines  to  believe  that  it  should  be  attributed  to  the  degree  of 
fluidity,  or  of  viscidity  communicated  to  the  water  by  the  different 
substances  dissolved  ;  thus  the  acetate  and  nitrate  of  lime,  with  the 
same  proportion  of  liquid,  form  more  viscid  solutions,  which  pass 
with  more  difficulty  through  a  filter,  than  the  alkaline  sulphates  and 
chlorides  ;  and  these  latter  salts  in  solution  were  absorbed  by  vege- 
tables in  greater  abundance  than  the  calcareous  salts.  Gum,  which 
imparts  more  viscidity  to  water  than  sugar,  is  also  less  capable  of 
being  absorbed.  Finally,  pure  water,  more  fluid  than  any  of  the 
solutions  tried,  was  also  that  which  vegetables  preferred  to  any 
other. 

In  the  results  of  the  incinerations  which  we  have  mentioned,  it  is 
obvious  that  in  many  plants  salts  are  met  vt^ith  in  very  small  propor- 
tion. This  circumstance  has  induced  several  physiologists  to  con- 
sider the  mineral  substances  found  in  vegetables  as  purely  accidental, 
and  consequently  unnecessary  to  their  existence.  M.  de  Saussure, 
however,  observes  that  this  scantiness  is  no  true  indication  of  their 
inutility,  and  he  mentions  that  the  phosphate  of  lime,  which  forms 
an  element  in  the  organization  of  an  animal,  does  not  probably 
amount  to  one  five-hundredth  part  of  the  entire  mass.  We  shall  add, 
that  as  the  phosphate  of  lime  was  met  with  by  M.  de  Saussure  in 
the  ashes  of  all  vegetables  which  he  examined,  and  as  all  the  analyses 
performed  since  the  original  labors  of  this  celebrated  chemist  have 
tended  to  confirm  the  accuracy  of  his  general  conclusions,  we  have 
no  ground  for  supposing  that  plants  could  exist  without  the  interven- 
tion of  saline  matter.  There  are  annual  plants  which,  when  burned, 
leave  more  than  10  per  cent,  of  residue  ;  and  vegetables  cultivated 
in  soils  free  from  saline  or  alkaline  matter,  and  watered  with  dis- 
tilled water,  though  they  will  live  and  ripen  their  seeds  in  some 
instances,  still  they  never  acquire  the  vigor  which  they  possess  when 
grown  in  a  fertile  soil. 

Duhamel  ascertained  that  marine  plants  languish  in  soils  destitute 
of  chloride  of  sodium ;  and  this  is  so  much  the  more  readily  oon- 


64  INORGANie    CONSTITUENTS, 

celved,  as  those  plants  which  furnish  ashes  abounding  ki  carbonate 
of  soda,  always  contain  organic  acids  combined  with  «he  alkaline 
base.  Borage,  the  nettle,  &c.,  thrive  only  in  places  where  they 
meet  with  nitrates  ;  and  it  is  easy  to  discover  that  plants  when  dried 
contain  a  notable  quantity  of  either  nitrate  of  potash  or  of  lime. 
The  vine  more  especially  requires  alkaline  dressings,  in  order  that 
the  large  quantities  of  potash  taken  from  the  soil  in  the  tartrate  of 
potash  of  the  grape  may  be  replaced. 

The  organic  acids,  so  different  in  their  composition  and  in  their 
properties,  which  are  met  wHh  in  the  different  vegetable  families, 
are  always  found  combined  in  the  state  of  neutral  or  acid  salts.  The 
proportion  of  base  combined  in  a  plant  with  a  vegetable  acid  may  be 
readily  ascertained  from  the  ashes ;  for  by  the  effect  of  incineration 
the  base  passes  into  the  state  of  an  alkaline  or  earthy  carbonate. 
The  vegetable  acids  undoubtedly  perform  important  functions  in  the 
organism  of  vegetables,  and  their  formation  probably  depends  on  the 
nfluence  of  the  bases  with  which  they  form  salts.  The  nature  of 
he  oxide  or  base  itself  appears  to  be  of  little  importance ;  it  is 
enough  that  it  be  present  in  the  plant.  It  is  known  that  certain  bases 
may  mutually  replace  each  other,  equivalent  for  equivalent. 

These  principles  assumed,  Prof.  Liebig  draws  a  remarkable  in- 
ference from  the  composition  of  the  ashes  of  different  kinds  of  wood  ; 
namely,  that  for  each  vegetable  family  the  sum  of  the  oxygen  of  the 
bases  combined  with  the  organic  acids  will  be  a  constant  number ; 
or,  in  other  words,  the  species  of  one  and  the  same  family  will  con- 
tain the  same  number  of  basic  equivalents  combined  with  vegetable 
acids. 

Thus,  100  parts  of  the  ashes  of  a  Breven  pine-tree,  analyzed  by 
Saussure,  contain : 

Carbonate  of  potash 3.60  Oxygen  of  the  potash 0.41  i 

lime 46.34  "  lirae 7.33V9.01ox. 

"  magnesia 6.77  "  magnesia 1.27) 

Carbonates 77.56.71 

The  ashes  of  a  pine  from  Mount  La  Salle  yielded  : 

Carbonate  of  potash 7.36  Oxygen  of  the  potash 0'85)ooic«- 

lime 51.Gd  "  lime 8.10|^'^*°^ 

"  magnesia 0-00 

58.55 

M.  Berthier  found  in  the  ashes  of  a  fir-tree  from  Allevard  the 
following  bases : 


Potash  and  Soda 16.8    Oxygen 3.42 

Lime 29-5        "        8.20 

Magnesia 3-2        "        1.20 


V12.J 


One  part  of  the  alkalies  containing  1.20  of  oxygen  was  combinea 
with  mineral  acids,  forming  sulphates,  phosphates,  and  a  chloride 
The  oxygen  of  the  bases  combined  with  the  carbonic  acid  is  cpn$e« 
quently  reduced  to  11  62. 

The  ashes  of  a  Norway  fir,  according  to  the  same  analyst,  con. 
taining : 


sa?.  66 


.2.40") 
.1.69 J 


Potash 14.10    Oxygen 

iSii:'::::::::::::::::: T^]^    -    ::::::::::::::::3:^^^-^^s^ 

Magne'iia 14.35        "        

51.45 

In  this  ash  the  bases  belonging  to  the  inorganic  salts  contain  1.37 
of  oxygen.  The  oxygen  of  the  bases  of  the  carbonates,  or  in  other 
words  of  the  bases  which  formed  organic  salts  in  the  tree,  therefore, 
becomes  11.47.  The  numbers  9.01  and  8.95  on  the  one  hand,  and 
11,62  and  11.47  on  the  other,  which  represent  the  quantity  of  oxy- 
gen of  the  whole  of  the  bases  in  the  ashes  obtained  from  plants  of 
the  same  species,  differ  so  little,  that  they  may  be  considered  as 
identical. 

Accurate  analyses  of  ashes  of  plants  of  the  same  species  grown 
in  soils  of  different  kinds,  will  determine,  says  Prof.  Liebig,  whether 
the  fact,  deduced  from  the  composition  of  the  ashes  of  the  pine  and 
fir-tree,  constitutes  a  definitive  law.* 

Be  this  as  it  may,  the  utility  of  alkalies  in  vegetation  cannot  be 
a  matter  of  doubt ;  many  usages  in  agriculture  prove  it  in  the 
clearest  manner;  and,  according  to  M.  Liebig,  the  fact  of  the  forma- 
tion of  the  organic  alkaloides  in  plants  affords  an  additional  proof 
of  it.  M.  Liebig  thinks  that  the  organic  alkalies  have  a  particular 
tendency  to  form  in  the  absence  of  mineral  bases ;  thus  potatoes 
which  germinate  in  cellars,  under  conditions  where  the  soil  cannot 
supply  them  with  potash,  soda,  or  lime,  develop  an  organic  alkali, 
solanine,  which  is  not  found  in  the  tubers  of  this  vegetable  as  usually 
cultivated.!  In  the  cinchonas,  quinine  and  cinchonine  are  combined 
with  quinic  acid  ;  but  there  is  frequently  found  quinate  of  lime  also. 
According  to  the  same  chemist,  the  latter  base  holds  the  place  of  a 
vegetable  alkali  in  the  organism  ;  the  more  prevalent  it  is  in  the  soil, 
the  less  rich  will  the  cinchona  plant  be  in  quinine  and  cinchonine.^ 
These  ingenious  views  certainly  deserve  the  careful  attention  of 
physiologists  ;  they  are  calculated  to  add  new  interest  to  the  study 
of  the  chemical  constitution  of  the  ashes  of  vegetables. 

The  inorganic  substances  contained  in  vegetables  evidently  come 
from  the  soil.  By  growing  seeds,  as  M.  Lassaigne  did,  in  flowers 
of  sulphur,  moistened  with  distilled  water,  the  plant  produced  con- 
tained neither  more  nor  less  saline  and  earthy  matter  than  was  origi- 
nally present  in  the  seed. 

The  water  absorbed  by  the  roots,  then,  becomes  charged  during 
Its  stay  in  the  ground  with  the  various  soluble  substances  which 
may  be  met  with  there,  and  which  generally  contribute  to  its  fer- 
tility ;  suck  especially  are  the  salts  derived  from  decomposed  organic 
substances.  Water  charged  with  small  quantities  of  the  soluble 
substances  diffused  through  the  soil,  constitutes  the  ascending  sap. 
When  it  ha  3  penetrated  the  plant,  immediately  after  its  passage  by 
the  spongi.les  of  the  roots,  perhaps  even  while  traversing  these 

*  Liebig,  Chimie  Organiqiie,  Introduction,  p.  cxL 
t  Liebig,  idem.  p.  cxiv. 

t  Liebig,  idem.  ^    ' 

6* 


66  TEANSITION  OF  INORGANIC  INTO  ORGANIC  MATTER. 

parts,  the  organic  matters  dissolved  in  the  fluid  appear  to  undergo 
important  modifications;  for  in  the  sap  substances  are  detected 
which  could  not  have  existed  in  the  water  which  moistened  the  soil. 
During  its  ascent  the  sap  increases  in  density,  as  was  ascertained 
by  Mr.  Knight,  according  to  whom,  the  sap  of  an  acer  platanoides^ 
taken  at  the  level  of  the  ground,  has  a  density  of  1.004  ;  at  67  feet 
above  it  this  density  becomes  1.008,  and  at  13  feet,  1.012.  From 
this  Mr.  Knight  concluded  that  the  sap  took  up  nutritive  matter 
deposited  in  the  vegetable  tissues  which  it  traversed  in  its  ascent.* 
We  have  already  seen  that  the  sap,  after  being  elaborated  in  the 
green  parts  of  trees,  takes  a  route  the  reverse  of  that  which  it  fol- 
lowed at  first,  and  we  therefore  spoke  of  this  modified  sap  as  the 
descending  sap.  It  is  very  possible  that  in  Knight's  observations 
the  liquid  examined  was  a  mixture  of  the  two  saps. 

We  should  not  be  over  hasty  in  concluding  that  the  action  of  the 
two  species  of  sap  was  exerted  separately  in  promoting  the  develop- 
ment of  the  plant ;  it  is  very  probable,  as  Dutrochet  thinks,  that  the 
modified  sap,  by  insinuating  itself  into  the  permeable  tissue  of  the 
vegetable,  is  continually  mixed  with  the  ascending  sap,  in  order  to 
concur  in  promoting  the  growth  of  the  buds.f  The  difficulty  of 
obtaining  each  particular  sap  separately,  if  such  a  separation  is  reallv 
possible,  prevents  the  analytical  conclusions  we  have  from  possess- 
ing all  the  accuracy  that  seems  desirable. 

Vauquelin  has  studied  the  sap  of  the  birch- tree,  of  the  hornbeam, 
of  the  beech,  of  the  chestnut,  and  of  the  elm. 

The  sap  of  the  hornbeam  {Carpinus  sylvestris)  was  obtained  in 
the  months  of  April  and  May.  At  this  period  it  is  colorless  and 
clear  as  water ;  its  taste  is  slightly  saccharine  ;  its  odor  resembles 
that  of  whey  ;  it  reddens  turnsole  paper.  The  sap  of  this  tree 
contains  water  in  very  large  quantity,  sugar,  extractive  matter,^ 
and  free  acetic  acid,  acetate  of  lime  and  acetate  of  potash,  in  very 
small  quantity. 

This  sap  left  to  itself  presents  in  succession  all  the  phenomena  of 
the  vinous  and  then  of  the  acetous  fermentation.^ 

The  sap  of  the  birch-tree  reddens  turnsole  intensely  ;  it  is  color- 
less, and  has  a  sweet  taste.  The  water  which  forms  the  greater 
part  of  it,  holds  in  solution  sugar,  extractive  matter,  acetate  of 
lime,  acetate  of  alumina,  and  acetate  of  potash. 

Whea  properly  concentrated  by  evaporation,  it  ferments  on  the 
addition  of  yeast,  and  then  yields  alcohol  on  distillation.  The  pre- 
sence of  the  acetate  of  alumina  may  appear  extraordinary  in  this 
sap,  for  this  reason,  that  alumina  has  not  yet  been  discovered  in  the 
ashes  of  the  birch-tree. 

Sap  of  the  beech,  {Fagus  sylvestris  )  The  analysis  was  made  in 
Marcli  and  April.  Tlie  color  of  the  sap  was  a  tawny  red  :  it  had 
the  taste  of  an  infusion  of  tanner's  bark  :  it  reddened  turnsole  slignt- 

*  Decandolle,  Physiologic,  t.  i.  p.  204. 

t  Dutrochet,  sur  la  Structure,  &c.  p.  36 

t  Probably  azotized. 

^  Vauquelin,  Annales  de  Chunie,  t.  xxxi.  p.  90,  lire  wMm. 


SAP  67 

\y.  Il  contained,  in  very  small  quantity,  acetate  of  lime,  acetate 
of  potash,  acetate  of  alumina,  extractive  matter,  tannin  acetic  acid, 
ind  gallic  acid. 

The  sap  of  the  chestnut-tree,  according  to  Vauquelin,  who,  foi 
want  of  a  sufficient  quantity  of  the  fluid.,  was  able  to  study  it  hut 
very  superficially,  contains  mucilage,  nitrate  of  potash,  and  the 
acetates  of  potash  and  lime. 

The  sap  of  the  elm  was  examined  at  three  periods ;  first,  at  the 
commencement  of  April,  then  some  days  after,  and  lastly,  a  month 
later.  At  the  beginning  of  April  its  color  was  yellow,  its  taste 
sweet  and  mucilaginous  ;  it  was  scarcely  acid.  Analysis  indicated  : 
water  1027.90,  acetate  of  potash  9.23,  organic  matter  1.06,  carbo- 
nate of  lime  0.80. 

At  the  second  period  it  contained  a  little  more  extractive  organic 
matter,  and  a  little  less  carbonate  of  lime  and  acetate  of  potash. 
The  last  examination  showed  that  these  two  salts  had  still  further 
diminished  in  quantity.  When  exposed  to  the  air,  the  sap  of  the 
elm  undergoes  decomposition,  and  becomes  alkaline  :  the  acetate  of 
potash  passes  into  the  state  of  carbonate. 

M.  Regimbeau  found  in  the  sap  of  the  vine*  bitartrate  of  potash, 
tartrate  of  lime,  mucilage,  and  free  carbonic  acid. 

The  sap  of  the  maple-tree  contains  a  very  considerable  quantity 
of  sugar.  In  Canada,  this  sap,  properly  treated,  yields  sugar  which 
is  identical  with  that  of  the  cane.  The  nature  of  the  sap  is  subject 
to  variations  ;  and  Duhamel  siates,  that  at  a  certain  season  it  loses 
its  saccharine  taste,  and  acquires  an  herbaceous  flavor.f 

Liebig  and  Will  detected  the  presence  of  ammoniacal  salts  in  the 
sap  of  the  maple  and  birch-tree,  and  in  the  tears  of  the  vine.  M. 
Blot  examined  the  sap  of  a  considerable  number  of  trees,  and  ascer- 
tained that  the  sugar  in  them  often  exists  in  two  different  states ;  in 
that  of  cane-sugar,  properly  so  called,  and  in  that  of  grape-sugar, 
which,  as  chemists  admit,  diflfers  from  the  former  only  in  the  pos- 
session of  an  additional  equivalent  of  water.  The  saps  which  M. 
Biot  examined,  contained  besides  some  animal  matter  (albumine) 
and  a  gummy  matter ;  he  found  no  free  carbonic  acid.  The  object 
which  he  had  in  view,  namely,  to  study  the  changes  which  occur  m 
the  nature  of  sugar,  did  not  lead  M.  Biot  to  notice  the  minute  quan- 
titiv3s  of  salts  with  organic  acids  which  Vauquelin  met  with  in  saps. 

The  trunk  of  a  walnut-tree,  tapped  on  the  11th  of  February, 
fielded  a  sap  containing  some  cane  sugar.  The  saps  of  the  syca- 
more, of  the  acer  negundo  and  of  the  lilac-tree,  contained  the  same 
species  of  sugar;  but  that  of  the  birch-tree  held  in  solution  some 
grape-sugar.  In  the  sycamore  and  birch-tree,  M.  Biot  observed 
an  extremely  interesting  fact.  He  ascertained,  on  felling  these  trees, 
that  the  greater  portion  of  the  descending  sap  was  accumulated  to- 
wards the  middle  of  the  trunk.  That  of  the  birch-tree  was  acid 
and  saccharine  ;  the  sap  of  that  portion  of  the  trunk  which  waa 

*  Journal  de  Pharmacie,  t.  xviii;  p.  36. 

i  Annales  de  1' Agriculture,  Franjaise,  t.  v.  2eme  s6rie,  p.  339. 


B8  TRANSITION  OF  INORGANIC  INTO  ORGANIC  MATTER. 

buried  in  the  ground,  contained  no  sugar,  but  a  substance  possessing 
the  principal  characters  of  gum.*  It  was  probably  an  effect  of  the 
season  ;  for  Knight  states,  that  he  never  could  discover  the  least 
trace  of  saccharine  matter  during  winter  in  the  alburnum  either  of 
the  stem  or  of  the  roots  of  the  sycamore. f 


SAP  OF  THE  BAMBUSA  GUADUAS. 

The  guaduas  grow-s  in  the  hot  and  marshy  countries  of  the  tropi- 
cal regions :  this  grass  frequently  attains  the  enormous  height  of 
from  65  to  100  feet.  Its  stem,  which  is  hollow,  is  divided  through 
its  entire  length  into  joints  spaced  rather  regularly  at  distances  of 
from  11  to  12  inches.  Each  joint  indicates  ihe  presence  of  a  woody 
partition,  which  seems  to  divide  the  stem  of  the  guaduas  into  so 
many  super-imposed  tubes.  On  perforating  it  immediately  above  a 
knot,  a  clear  limpid  fluid  flows  out,  which  cannot  be  distinguished 
from  the  purest  water.  This  indeed  is  a  store  of  water  of  which 
travellers  have  frequently  availed  themselves.  This  sap,  as  I  have 
been  assured  by  the  inhabitants  of  the  countries  where  I  observed 
the  guaduas,  never  completely  fills  the  hollow  space  included  be- 
tween two  joints.  Analysis  satisfied  me  that  the  sap  of  the  guaduas 
is  almost  pure  water.  Re-agents  detected  merely  traces  of  sulphates 
and  chlorides.  On  evaporating  a  considerable  quantity  of  it,  I  was 
able  to  discover,  independently  of  these  traces  of  soluble  salts,  a 
very  small  proportion  of  organic  matter  and  of  silica  ;  the  latter  sub- 
stance is  probably  the  element  which  predominates  in  the  sap  of  the 
guaduas. 

SAP  OF  THE  BANANA  PLANT,  (mUSA  PARADISICA.) 

The  sap  of  the  banana  possesses  a  well-marked  astringent  taste  : 
It  reddens  tincture  of  litmus.  Immediately  after  escaping  from  the 
plant,  it  is  limpid  and  colorless,  like  water  ;  nevertheless,  it  possesses 
the  property  of  imparting  a  yellow  color  to  stuffs  immersed  in  it. 
Exposed  to  the  air  it  becomes  turbid,  and  throws  down  flocculi  of  a 
dirty  rose  color.  It  is  to  the  action  of  oxygen  that  this  deposite  is 
owing ;  for  it  takes  place  only  in  contact  with  the  air.  After  the 
formation  of  this  deposite,  the  sap  no  longer  colors  stuffs  immersed 
in  it.  From  a  chemical  examination  which  I  instituted  of  the  sap 
of  the  banana,  during  my  sojourn  on  the  banks  of  the  Magdalena,  I 
think  I  may  state  that  it  contains  gallic  acid,  acetic  acid,  chloride 
of  sodium,  salts  of  lime  and  potash,  and  silica. 

The  sap  of  vegetables,  elaborated  during  its  passage  through  the 
leaves,  acquires  additional  consistence.  It  generally  contains  pecu- 
liar principles,  which  are  the  result  of  this  elaboration,  and  these 
now  constitute  the  liquid  which  is  usually  designated  by  the  name  of 
ihe  particular  juice  of  the  plant  from  which  it  is  procured.     Thia 

•  Annales  du  Mus6um  d'Histoire  Naturalle,  t.  il. 

^  Knight,  quoted  in  Annales  de  rAgriculttue  Franf aise,  t  ▼.  3e  t^rie,  p.  338 


SAP.  69 

proper  juice  or  sap  is  generally  obtained  by  making  an  incision  which 
penetrates  a  little  below  the  bark. 

The  characters  and  properties  of  the  elaborated  or  descendingrsap. 
are  extremely  various.  It  may,  however,  be  divided  into  milky  sap^ 
saccharine  sap,  gummy  sap,  and  resinous  sap,  according  to  the  na- 
ture of  the  juices  dissolved  or  .suspended  in  the  liquid.  As  several 
of  the  peculiar  juices  of  vegetables  contain  principles  employed  in 
the  arts  or  in  medicine,  they  have  been  more  carefully  studied,  and 
their  history  is  more  complete  than  that  of  the  ascending  saps.  I  do 
not  propose  to  give  a  monograph  of  these  juices  ;  in  this  place  I 
shall  only  mention  those  which  have  been  examined  with  some  care. 

MILKY    SA.PS. 

The  milky  saps,  as  their  name  indicates,  have  the  appearance  of 
milk  ;  they  owe  this  milky  appearance  to  globules  of  insoluble  mat- 
ter, minutely  divided,  and  suspended  in  a  liquid. 

SAP    OF    THE    PAPAW-TREE,    (CARICA    PAPAYA.) 

The  carica  papaya  grows  in  tropical  regions.  The  sap,  which  is 
extracted  from  the  fruit  by  incision,  is  white,  and  excessively  vis- 
cous. In  a  specimen  of  this  sap,  which  came  from  the  Isle  of  France, 
Vauquelin  found  water  in  large  quantity,  and  also  a  matter  having 
the  chemical  properties  of  animal  albumen,*  and  lastly  fatty  matter. 

I  took  occasion  to  verify  the  correctness  of  the  results  obtained  by 
Vauquelin,  on  the  milk  of  the  fruit  of  the  carica  papaya,  during  my 
sojourn  at  Caraccas,  where  I  examined  the  sap  which  flowed  from 
the  trunk  of  the  tree  itself.  This  sap  is  less  milky,  and  much  more 
fluid  than  that  which  flows  from  the  fruit ;  it  had  the  appearance  of 
milk-and-water.  Its  odor  is  rather  nauseating,  even  when  coming 
from  the  plant ;  its  taste  slightly  sour.  When  exposed  to  the  air  it 
soon  coagulates.  It  contains  a  considerable  portion  of  matter,  which 
may  be  compared  to  animal  fibrine,  and  sugar,  wax,  and  resin,  in 
small  quantities. 

Evaporated  and  burnt,  it  leaves  a  saline  residue.  This  juice  is 
employed  by  the  inhabitants  for  medical  purposes. 

SAP    OF    THE    COW-TREE. 

Among  the  number  of  astonishing  vegetable  productions  observed 
in  the  equinoctial  regions,  is  a  tree  which  yields  a  milky  juice  in 
abundance,  similar  in  its  properties  to  the  milk  of  animals.  At  the 
time  I  left  Europe,  M.  de  Humboldt  expressly  recommended  me  to  di- 
rect my  attention  to  the  milk  of  the  cow-tree.  A  short  time  after  my 
arrival  in  the  Cordilleras,  on  the  shore  of  Caraccas,  M-  Rivero  and 
myself  were  able  to  comply  with  the  wishes  of  the  distinguished 
traveller.! 

The  milk  we  examined  came  from  the  Palo  de  Lechc,  the  milk- 
tree,  which  is  extremely  common  in  the  environs  of  Maracaibc. 

*  Vauquelin,  Annales  de  Chiinie,  t.  xlix.  p.  219,  Ire  s*rie. 

t  Bivero  and  Boussingault,  Annales  de  Chim.  et  de  Phys.  t.  zzxUi.  p.  229,  2e  uixit 


70  FRANSITION  OF  INORGANIC  INTO  ORGANIC  MATTER. 

Vegetable  milk  possesses  the  same  physical  characters  as  that  of 
the  cow,  with  this  sole  difference,  that  it  is,  in  a  slight  degree,  vis- 
cous ;  its  flavor  is  agreeable,  slightly  balsamic.  With  respect  to 
chemical  properties,  these  differ  perceptibly  from  those  which  are 
peculiar  to  animal  milk.  Acids  do  not  curdle  it ;  alcohol  scarcely 
coagulates  it. 

Under  the  action  of  gentle  heat,  light  pellicles  are  seen  to  form 
on  the  surface  of  vegetable  milk.  On  evaporating  it  over  a  water 
bath,  an  extract  is  obtained  resembling  fritters  ;  and  if  the  action  of 
the  fire  be  continued  for  a  certain  time,  oily  drops  are  observed, 
which  increase  in  proportion  as  the  water  is  dissipated,  and  ulti- 
mately form  a  liquid  of  an  oily  appearance,  in  which  a  fibrinous 
substance  floats,  which  dries  and  becomes  tough  in  proportion  as  the 
temperature  increases.  An  odor  is  then  diffused,  exactly  like  that 
of  meat  frying  in  fat. 

By  the  mere  action  of  heat,  then,  the  milk  of  the  Palo  de  Leche 
is  separated  into  two  distinct  portions :  the  one  fusible,  of  a  fatty 
nature,  the  other  fibrinous,  and  presenting  all  the  characters  of  ani- 
mal substances. 

If  the  evaporation  of  vegetable  milk  is  not  carried  too  far,  i«e 
fatty  matter  may  be  obtained  unchanged  ;  it  then  possesses  the  fol- 
lowing properties ; — it  is  white,  translucent,  sufficiently  solid  to 
resist  the  impression  of  the  finger ;  it  fuses  at  140°  (Fahr. ;)  boiling 
alcohol  dissolves  it  completely  ;  it  is  equally  soluble  in  potash. 

The  fibrinous  matter  presents  all  the  characters  of  fibrine,  obtained 
from  the  blood  of  animals  ;  for  this  reason  we  have  called  it  fibrine. 
In  fact,  when  put  on  a  hot  iron,  it  swells  up,  fuses,  and  becomes 
carbonized,  exhaling  the  odor  of  grilled  meat.  Treated  with  weak 
nitric  acid,  it  gives  out  nitrogen  gas ;  by  distillation,  it  disengages 
ammoniacal  vapors  in  abundance. 

The  presence  and  nature  of  this  animalized  matter  in  the  milk 
of  the  cow-tree,  explains  how  this  milk  acquires  the  odor  of  old 
cheese  on  becoming  changed.  We  considered  the  fatty  matter  of 
the  milk  as  analogous  to  beeswax ;  I  may  even  say  that  we  made 
wax-candles  of  it.  However,  the  property  of  being  completely  dis- 
solved in  hot  alcohol,  combined  with  its  ready  solubility  in  potash, 
establish  a  well-marked  difference  between  it  and  the  wax  of  insects. 
This  is  a  question  which  can  only  be  completely  cleared  up  by  ele- 
mentary analysis,  and  we  were  altogether  without  the  means  of 
making  any  minute  examination  of  the  wax  of  vegetable  milk. 

In  the  water  which  holds  the  wax  and  animal  matter  in  suspension, 
we  met  with  some  saline  substances  and  a  free  acid,  the  nature  of 
which  we  were  unable  to  determine.  We  did  not  succeed  in  detect- 
ing the  presence  of  caoutchouc  in  vegetable  milk.  According  to 
our  researches  this  milk  should  contain  : 

1.  A  fatty  substance  similar  to  beeswax ; 

2.  An  animal  substance,  similar  to  animal  fibrine  ; 

3.  Water,  salts,  a  free  acid,  and  a  little  sugar. 


SAP.  7 

By  incineration,  we  obtained  ashes  from  the  milk  in  which  wer* 
found  phosphate  of  lime,  lime,  magnesia,  and  silica. 

During  their  excursions  in  the  Cordilleras,  the  inhabitants  fre 
quently  drink  the  milk  of  the  cow-tree.  M.  de  Rivero  and  mysell 
also  used  it  during  our  sojourn  at  Maracaibo. 

The  tree  which  produces  the  milk  which  we  examined,  is,  accord 
ing  to  M.  de  Humboldt,  the  galactodendron  dulce,  of  the  family  of 
the  verticas,  or  fig-trees.  But  several  trees  are  known  in  tht 
mountains  along  the  coast,  which  yield  a  milky  juice,  and  which 
are  often  confounded  with  that  just  described.  For  instance,  in  the 
environs  of  Maracaibo,  according  to  M.  Desvaux,*  the  clusia  galac- 
todendron yields  an  abundance  of  very  pleasant  vegetable  milk  ; 
this  milk,  however,  does  not  seem  to  contain  much  animalized  matter; 
at  least  it  does  not  putrefy  perceptibly,  and  instead  of  the  waxy 
matter,  a  substance  much  less  fusible  and  of  a  resinous  character  is 
procured  from  it. 

MILKY    SAP    OP   THE    HURA   CREPITANS,  (aJUAPAR.) 

The  sap  of  the  hura  crepitans  is  dreaded,  and  not  without  good 
reason  ;  it  is  enough  to  be  exposed  to  the  emanations  of  this  milky 
juice,  when  recently  extracted,  to  be  seriously  affected  by  it. 
The  use  which  is  made  of  it,  to  poison  the  water  of  rivers,  in 
order  to  obtain  the  fish,  is  a  suflUcient  indication  of  its  pernicious 
qualities.! 

This  vegetable  sap  would  perfectly  resemble  that  of  the  cow-tree, 
if  it  were  not  slightly  yellowish.  It  has  no  smell ;  its  taste,  which 
is  very  little  marked  at  first,  soon  causes  very  violent  irritation.  It 
reddens  the  color  of  turmeric  ;  mineral  acids  produce  in  it  a  white 
and  viscous  curd  ;  the  surrounding  fluid  is  clear  and  of  a  yellow 
color.  Left  to  itself,  the  milky  sap  of  the  hura  crepitans  yields  all 
the  products  of  the  putrefaction  of  caseum.  It  contains:  1.  An 
azotized  substance  similar  to  gluten,  or  caseum.  2.  A  vesicating 
oil,  3.  A  crystallized  substance,  having  an  alkaline  reaction.  4. 
Malate  of  potash.  5.  Nitrate  of  potash.  6.  A  salt  of  lime,  (the 
malate  ?)     7.  An  odorous  azotized  principle. 

MILKY  SAP  OF  THE  POPPY,  (oPIUM.) 

The  milky  sap  which,  by  concreting,  furnishes  the  opium  of  com- 
merce, is  obtained  by  making  longitudinal  incisions  in  the  capsules 
of  the  poppy.  The  operation  takes  place  before  the  fruit  is  ripe, 
and  after  the  fall  of  the  flower. 

*  Benseignements  communiques  par  M.  Adolphe  Brongniart. 

t  Bivero  et  BoiHsinguult,  Aimales  de  Chim.  et  de  Phys.  t.  xviii.  p.  430,  2e  s6rie. 

What  1  shall  no.v  state  may  give  an  idea  of  the  energy  with  which  this  milky  juice 
acts  on  the  animal  economy :  when  M.  Bivero  and  myself  examined  the  milk  of  the 
hura  crepitant,  we  became  affected  with  er>-sipela8 ;  the  afiection  continued  for  sev- 
eral days.  The  milk  had  l>een  sent  to  us  in  guaduas  by  Dr.  Boulin  ;  the  messenger 
who  brought  it  was  seriously  affected  byit ;  and  along  the  road  the  inhabitants  of  tb« 
kouses  where  he  lodged  felt  the  same  effects. 


72  TRANSITION  OF  INORGANIC  INTO  ORGANIC  MATTER. 

The  concrete  sap  is  brown,  firm,  of  an  acrid  and  bitter  taste,  and 
of  a  peculiar  sickening  odor.  Opium  contains  a  number  of  principles 
the  study  of  which  has  exercised  for  a  considerable  time  the  inge- 
nuity of  the  most  skilful  chemists.  It  was  in  this  substance  that 
Sertuerner  found  the  first  vegetable  alkali  which  was  discovered, 
morphine.  After  numerous  trials  made  on  opium,  it  was  found  to 
contain  : — 1.  Morphine,  (vegetable  alkali.)  2.  Codeine,  (the  same.) 
3.  Narceine.  4.  Meconine.  5.  Para-morphine.  6.  Pseudo-mor- 
phine. 7.  Meconic  acid.  8.  Resin.  9.  Fatty  matters.  10.  Caout- 
chouc. 11.  Gum.  12.  Bassorine.  13.  Ulmine.  14.  Woody  sub- 
stance.    15.  Mineral  salts  with  bases  of  lime,  magnesia,  and  potash. 

MILK  OF  THE  PLUMERIA  AMERICANA. 

The  plumeria,  'when  one  of  its  branches  is  broken,  yields  a  con- 
siderable quantity  of  milky  juice.  At  the  time  when  I  examined 
this  juice,  the  tree  was  entirely  destitute  of  leaves.  The  milk  of  the 
plumeria  is  perfectly  white  ;  it  is  very  fluid  when  it  flows  from  the 
plant,  but  soon  after  deposites  a  crystalline  sediment.  The  taste  is 
slightly  bitter,  and  it  has  an  acid  reaction.  The  milk  of  the  plumeria 
appears  to  contain  no  animalized  matter.  I  was  only  able  to  detect 
a  very  large  proportion  of  resinous  matter  held  in  solution  or  sus- 
pended in  water ;  and  indications  of  potash,  lime,  and  magnesia, 
combined  with  an  organic  acid. 

SAP  OF  THE  CAOUTCHOUC  TREE. 

Caoutchouc  is  found  in  the  sap  of  many  trees,  and  in  that  of  a 
great  number  of  herbaceous  plants ;  but  it  is  the  havea  caoutchouc, 
the  jatropha  elastica,  peculiar  to  South  America;  the  ftcus  Indica, 
and  the  artocarpus  integrifolia,  which  grow  in  the  East  Indies,  that 
yield  the  caoutchouc  so  well  known  in  commerce,  and  which  has 
been  converted  to  so  many  useful  purposes  in  the  arts. 

The  caoutchouc  tree  is  particularly  common  in  Choco  and  forests 
near  the  equator.  To  obtain  the  elastic  gum,  the  Indians  incise  the 
tree  below  the  bark,  when  there  issues  a  copious  discharge  of  milky 
sap,  which  will  remain  fluid  for  a  considerable  lime,  if  it  be  kept 
from  contact  with  the  air.  I  have  seen  it  carried  to  great  distances, 
in  wooden  vessels  hermetically  closed.  When  spread  out  in  thinnish 
layers,  it  soon  coagulates,  and  acquires  the  singular  elasticity  which 
characterizes  caoutchouc.  The  action  of  the  oxygen  of  the  air  may 
possibly  have  some  influence  in  producing  this  coagulation,  un- 
less what  I  am  about  to  state  be  the  effect  of  a  prompt  evaporation 
of  the  water  of  the  sap.  I  have  often  made  a  small  incision  in  the 
trunk  of  an  hcEvea  from  which  milk  immediately  flowed,  and  by  rea- 
son of  its  viscidity,  trickled  down  the  tree  in  a  stream  of  a  certain 
thickness  ;  this  milk  was  at  first  extremely  fluid,  but  after  from  one 
to  two  minutes'  exposure  to  the  air,  it  suddenly  coagulated,  so  that 
on  raising  the  drop  from  the  lower  end,  I  obtained  a  long  string  or 
riband  of  perfectly  elastic  caoutchouc. 


SA?.  73 

In  Guiana  the  Indians  fashion  the  caoutchouc  into  the  bottles 
which  are  so  common  in  trade  :  they  make  a  clay  mould,  and  this 
they  cover  by  immersing  it  in  the  milk  freshly  drawn  from  the  tree ; 
they  allow  it  to  coagulate,  which  it  does  very  speedily,  especially  if 
it  be  exposed  to  the  smoke  of  a  wood  fire.  This  first  layer  being 
coagulated,  they  c(mtinue  the  same  process  until  the  desired  thick- 
ness is  attained.  The  mould  is  then  broken  and  taken  out  piece  meal 
from  the  interior  of  the  caoutchouc  bottle  which  has  been  formed. 

The  workmen  of  Quito,  who  are  very  dexterous  in  manufacturing 
caoutchouc,  make  shoes  and  buskins  of  it,  by  applying  it  in  the 
milky  state  over  moulds  of  the  proper  fashion.  They  also  render 
tissues  impervious  by  spreading  it  in  the  same  state  between  two 
pieces  of  stuff  or  cloth;  the  interposed  milk  becomes  coagulated,  and 
forms  a  thin  elastic  lamina,  very  preferable  to  the  caoutchouc  applied 
by  the  aid  of  solvents. 

The  Indians  of  Choco  sometimes  procure  this  substance  by  felling 
the  tree,  and  receiving  the  milk,  which  then  flows  in  a  stream,  into 
large  wooden  moulds,  generally  formed  from  a  hollow  stem  of  the 
guaduas.  By  keeping  the  mould  open,  the  milky  mass  coagulates 
after  some  time.  Several  of  these  masses  of  caoutchouc,  which 
were  brought  to  me  by  the  Indians  of  the  Chami  nation,  were  but 
slightly  elastic  ;  their  color  also  was  extremely  deep.  It  is  probable, 
that  by  proceeding'  in  this  way,  the  milky  juice  is  mixed  with  large 
quantities  of  the  internal  sap  which  is  much  less  milky. 

Several  trees  in  the  valley  of  the  Magdalena  which  bear  the  name 
of  caoutchouc,  which,  however,  are  neither  the  hoevea,  nor  the  ja- 
tropha,  also  yield  a  coagulable  juice,  which  may  be  confounded  with 
the  elastic  gum ;  it  is,  I  believe,  caoutchouc  combined  with  a  large 
quantity  of  wax,  and  probably  also  of  resin;  this  caoutchouc  pos- 
sesses but  little  elasticity. 

M.  Faraday  found  in  the  milk  of  the  hcevea,  in  100  parts  : 

Water 56 

Caoutchouc 32 

Bitter  azotized  matter  soluble  in  water  and  alcohol 7 

A  substance  soluble  in  water  and  alcohol  (sugar)  «  3 

100 
As  this  milk  will  remain  fluid  for  a  considerable  time,  provided  it 
ne  protected  from  the  air,  advantage  has  been  taken  of  this  property 
to  convey  it  to  Europe.     It  is  sent  in  well-filled,  hermetically-sealed 
bottles. 

GUMMY  AND  RESINOUS  SAPS. 

I  place  under  this  head  the  saps  of  those  trees  which  yield  gum 
from  incisions  in  their  trunk,  as  the  acacia  vera  and  acacia  Arabica^ 
which  grow  in  Arabia,  and  from  w^hich  gum-arabic  is  obtained  ; 
acacia  Senegal,  which  also  furnishes  a  species  of  gum.  In  general, 
in  very  warm  countries,  the  mimosas  produce  gummy  matters  in 
abundance. 

The  elaborated  sap  of  the  coniferae  and  terebinthaceae  consists 
ihiofly  of  resinous  matter,  dissolved  in  an  essential  oil  cbmposed  of 

7 


74  TRANSITION  OF  INORGANIC  INffO   ORGANIC  MfLTTER. 

carbon  and  hydrogen,  similar  to  the  essence  of  turpentine.  The 
balsams  of  Peru  and  Tolu  are  obtained  by  incising  the  bark  of  the 
trees  which  produce  them.  In  Choco,  where  I  have  seen  numerous 
incisions  made  in  the  lower  part  of  the  trunk  of  the  Tolu  trees,  the 
balsam  flows  slowly,  on  account  of  its  thickness ;  it  does  not,  ap- 
parently, contain  any  water. 

SACCHARINE  SAPS. 

The  sap  of  the  fraxinus  amu*,  and  that  of  the  fraxinus  rotundu 
folia,  yield  manna  on  drying  or  becoming  thick.  The  sap  of  several 
palms  contains  a  considerable  quantity  of  saccharine  matter.  At 
Java,  for  instance,  crystalline  sugar  is  extracted  from  the  arenga 
saccharifera.  In  several  places,  the  sap  of  palm-trees  is  subjected 
to  fermentation  in  order  to  prepare  vinous  liquors. 

The  Cocos  butyracea  {palma  de  vino)  is  very  common  in  the  valley 
of  the  Rio-Grande  de  la  Magdalena.  From  a  superficial  examina- 
tion which  I  made  of  it,  its  sap  contains  sugar,  an  azotized  matter, 
and  some  soluble  salts. 

By  fermentation,  it  produces  a  vinous  liquor  sufficiently  alcoholic 
to  produce  intoxication.  In  order  to  procure  it,  the  natives  of 
Benadillo  first  fell  the  tree,  taking  care,  when  it  is  down,  to  give  the 
trunk  a  slight  inclination  from  the  summit  towards  the  lower  extremity 
or  foot.  They  then  make  a  hole  towards  the  base  of  the  trunk  suf- 
ficiently large  to  hold  from  fifteen  to  eighteen  pints,  the  orifice  of 
which  they  plug  up  with  leaves.  The  woody  tissue,  to  all  outward 
appearance,  contains  but  little  moisture  ;  but  in  ten  or  twelve  hours 
after  the  operation,  the  cavity  is  found  full  of  a  liquid,  of  a  well- 
marked  vinous  odor,  and  of  a  sourish  taste,  owing  probably  to  the 
carbonic  acid  which  is  disengaged  in  large  quantity.  The  wine  thus 
obtained  is  rather  agreeable.  A  palm-tree  of  from  50  to  60  feet  in 
height,  and  of  which  the  trunk  towards  the  base  is  from  20  to  24 
inches  in  diameter,  will  yield  from  twenty  to  thirty  pints  of  wine  in 
twenty-four  hours  during  ten  or  twelve  days.  The  wine  must  not 
be  allowed  to  remain  too  long  after  it  has  collected,  otherwise  it 
becomes  sour. 

Sugar  is  far  from  being  the  only  useful  substance  afforded  by 
palms.  There  are  several  of  these  trees  which  are  truly  astonishing 
by  reason  of  the  many  important  uses  to  which  they  may  be  applie-  ; 
and  it  is  not  without  reason  that  the  missionaries  have  styled  the 
palm,  the  tree  of  Providence,  the  bread  of  life.  Such  more  espe- 
cially is  the  Cocos  maurilia,  which  grows  in  the  plains  of  the  Apure 
and  Oronoko ;  its  young  shoots  serve  as  aliment ;  from  its  fruit, 
while  still  green,  a  farinaceous  food  may  be  obtained  ;  and  when 
perfectly  ripe,  it  yields  oil  in  abundance.  Hammocks  and  various 
kinds  of  cloth  are  made  of  the  fibrous  portion  of  the  bark  of  this 
tree  ;  the  young  leaves  serve  to  make  hats,  mats,  and  sails  for  ships  ; 
the  tissue  which  surrounds  the  fruit  furnishes  the  Indians  with 
clothing  ;  the  sap  ferments  and  yields  wine  ;  the  trunk  before  fruc- 
tification contains  an  amylaceous  marrow,  of  which  bread  is  made  ; 
tki»  marrow,  on  becoming  putrid,  produces  a  vast  multitude  of  larg« 


CHEMICAL  CONSTITUTION  OF  VEGETABLES.         75 

white  worms  which  the  Indians  value  as  a  most  delicate  dish  ;  finally, 
the  woody  part  of  the  mauritia  aflfords  excellent  timber  for  building. 
It  is  not  necessary  to  enumerate  farther  the  principles  produced 
by  vegetables ;  we  must  now  study  them  in  reference  to  their  ele- 
mentary composition. 


CHAPTER  II. 

OF   THE   CHEMICAL   CONSTITUTION    OF   VEGETABLE    SUBSTANCES 

From  the  very  first  period  of  vegetable  life,  during  germination, 
the  immediate  principles  which  constitute  the  seed  are  destroyed  or 
changed.  The  young  plant,  in  developing  its  organs,  creates  new 
substances,  which  are  added  to  the  tissues  already  existing,  so  as  to 
complete  or  extend  them.  In  order  to  account  for  the  productions 
or  changes  which  take  place  in  the  organism  of  vegetables,  it  is  ex- 
pedient first  to  study  the  intimate  nature  and  general  characters  of 
the  materials  which  compose  them.  Unfortunately,  in  the  present 
state  of  science,  this  study  is  as  yet  but  little  advanced  ;  and,  not- 
withstanding the  eflTorts  which  chemical  physiology  has  made  in 
recent  times,  there  still  remain  numerous  and  important  questions 
to  be  solved. 

Carbon,  hydrogen,  oxygen,  azote,  combined  in  some  cases  with 
minute  quantities  of  sulphur  or  phosphorus,  are  the  only  elements 
required  by  nature  to  give  rise  to  that  almost  endless  variety  of 
vegetable  substances,  so  different  in  their  properties,  as  well  as  in 
their  uses.  In  the  food  which  sustains  the  life  of  animals,  as  in  the 
virulent  poison  which  destroys  it,  these  same  elementary  bodies  are 
always  found  combined  in  various  and  dissimilar  proportions. 

The  immediate  principles  of  the  vegetable  kingdom  may  be 
divided  into  three  groups,  if  we  look  to  the  number  of  the  elements 
which  constitute  these  principles  as  they  exist  in  the  several  bodies  : 

1°.   Quartcrnari/,  containing  carbon,  hydrogen,  oxygen,  azote. 

2°.   Ternary,  containing  carbon,  hydrogen,  oxygen. 

3°.  Binary,  containing  carbon  and  hydrogen,  or  carbon  and  oxy- 
gen, or  carbon  and  azote. 

It  is  by  the  examination  of  the  immediate  principles  which  exist 
m  the  seed,  that  we  should  approach  the  study  of  the  composition 
of  vegetables ;  and  this  the  more,  as  we  shall  find  these  principles 
diffused  throughout  the  organs  of  plants.  Once  we  shall  have  fully 
considered  their  properties  and  their  elementary  composition,  it  will 
be  sufficient  merely  to  indicate  where  they  are  to  )e  met  with  in 
the  organism. 


76  CHEMICAL  CONSTITUTION  OF  VEGETABLES. 


§  1.  QUARTERNARY  AZOTIZED  PRINCIPLES  OF 
VEGETABLES. 

It  has  now  for  some  considerable  time  been  ascertained  that 
several  seeds  contain  azote,  inasmuch  as  azotized  matters,  nearly 
similar  to  those  obtained  from  the  tissues  of  animals,  can  be  extract- 
ed from  them.  M.  Gay-Lussac  expressed  this  fact  in  the  most 
general  manner,  by  laying  it  down  "as  a  law  that  every  seed  contains 
a  principle  abounding  in  azote.* 

Azotized  animal  matters,  when  heated  in  close  vessels,  yield  an 
ammoniacal  product  ;  and  to  satisfy  ourselves  of  the  generality  of 
the  law  laid  down  by  Gay-Lussac,  all  that  is  necessary  is  to  subject 
any  seed  whatever  to  dry  distillation. 

We  do  not  always,  indeed,  obtain  an  ammoniacal  liquor  hnmedi- 
ately  in  this  way  ;  rice,  for  instance,  when  heated  in  a  retort,  yields 
a  product  having  an  acid  reaction  ;  but  it  is  easy  to  demonstrate  in 
the  acid  liquor,  the  presence  of  ammonia  by  the  addition  of  lime, 
which  at  once  sets  it  free.  Peas,  kidney-beans,  in  a  word  all  the 
legutnens  hitherto  experimented  on,  yield  a  liquor  directly,  having  a 
highly  alkaline  reaction.  These  differences,  in  the  products  of  the 
dry  distillation  of  seeds,  are  explained  in  a  very  natural  way. 
Throwing  the  husk  out  of  the  question,  we  may  consider  a  seed  a? 
formed  of  two  parts  ;  one,  non-azotized,  possessing  a  ternary  com- 
position, and  yielding  by  the  action  of  heat  a  liquid  with  an  acid  re- 
action ;  the  other  having  a  quarternary  composition,  consequently 
azotized,  and  yielding  an  ammoniacal  liquor,  so  that  the  acid  or  alka- 
line reaction  of  the  product,  really  depends  on  the  predominance  of 
one  or  other  of  these  two  distinct  ingredients. 

M.  Gay-Lussac  subjected  every  kind  of  seed  he  could  procure  to 
distillation,  and  all  yielded  ammonia  either  directly  or  indirectly.  I 
shall  add,  that  the  numerous  analyses  which  I  have  had  occasion  to 
make  for  several  years  back  support  the  generality  of  the  principles 
laid  down  by  the  above  celebrated  chemist.  M.  Payen  has  come  to 
the  same  conclusion,  and  has  further  shown  that  at  the  period  of 
germination  the  azotized  matter  of  seeds  is  determined  towards  the 
parts  that  are  most  recently  organized.  Thus  the  spongioles  situ- 
ated at  the  extremities  of  the  radicles  constantly  produce  ammoniacal 
vapors  during  their  destructive  distillation  by  heat,  even  though  pro- 
ceeding from  seeds  which,  when  distilled,  yield  an  acid  liquor  where- 
in ammonia  only  becomes  sensible  on  the  addition  of  lime. f 

The  animalized  or  azotized  substance  is  extracted  readily  enough 
from  certain  seeds,  and  has  consequently  been  known  to  exist  in 
them  for  a  very  long  time.  It  is  found  in  wheat,  for  example,  in  dif- 
ferent states,  and  is  obtained  with  great  ease  by  simply  kneading  a 
mass  of  dough  under  a  small  stream  of  water  by  which  the  starch  is 
carried  off,  and  by  and  by  there  remains  in  the  hand  a  grayish  highly 

•  Gay-Lussac,  Annales  de  Chimie  et  de  Physique,  t  liii.  p.  110,  3e  s6rie 
t  Payen,  M^moire  sur  la  cooipoaitioa  chimique  des  v6g6taui,  p-  7. 


AZOTIZED   PRINCIPL5S.  77 

elastic  substance  of  a  peculiar  heavy  odor;  this  is  the  gluten  of 
chemists.  By  this  simple  process  of  analysis,  however,  we  are  en- 
abled in  many  cases  to  estimate  the  quality  of  a  sample  of  flour  with 
reference  to  its  richness  in  gluten,  a  substance  which  is  rightly 
considered  as  the  most  essential  among  the  nutritive  elements  of  the 
cereals. 

The  washings  collected  and  allowed  to  stand,  soon  become  clear: 
the  starch  which  was  suspended  in  the  liquid  subsides,  accompanied 
by  flakes  of  an  animalized  matter.  If  the  clear  liquor  be  decanted 
and  boiled,  a  white  froth  appears  upon  its  surface,  which,  skimmed 
off,  is  found  to  have  the  appearance  of  coagulated  white  of  egg,  and 
which,  in  fact,  has  all  the  characters  of  animal  albumen.  The  water 
from  which  the  albumen  is  solidified,  necessarily  contains  all  the 
soluble  substances  of  the  flour.  On  evaporation,  it  leaves  substances 
similar  to  gum  and  sugar,  and  traces  of  saline  matters. 

With  the  exception  of  the  starch,  which  contains  very  little  for- 
eign matter,  the  different  substances  obtained  by  this  process  of 
washing  are  far  from  being  in  a  state  of  purity.  I  have  said  that  all 
seeds  contain  fatty  substances,  but  in  the  products  of  the  operation 
just  described,  no  oily  matter  was  detected.  As  it  cannot  be  discov- 
ered in  perceptible  quantity  in  starch,  nor  in  the  substances  soluble 
in  water,  it  must  remain  attached  to  the  gluten  ;  and  this  is  actually 
the  case.  The  gluten,  the  coagulated  albumen  then,  are  not  pure 
proximate  principles ;  fiit  or  oil  may  be  obtained  from  them ;  and 
further,  by  examining  common  gluten  carefully,  we  learn  that  it  con- 
tains several  azotized  substances,  which  differ  from  one  another.  By 
boiling  crude  gluten  with  alcohol  we  ultimately  obtain  a  fibrous  gray- 
ish residue,  called  by  M.  Dumas  vegetable  fibrine.  On  cooling,  the 
alcoholic  liquor  lets  fall  a  substance  which  in  its  properties  resembles 
the  caseum  or  curd  of  milk.  Lastly,  if  the  cold  alcoholic  solution 
be  concentrated,  a  pultaceous  substance  separates  from  it,  called  by 
Messrs.  Dumas  and  Cahours  glutine. 

Analysis,  accordingly,  indicates  the  presence  of  four  azotized  sub- 
stances in  wheat ;  and  when  these  are  all  combined  in  the  mass  of 
gluten  obtained  by  washing  a  lump  of  dough,  they  retain  fatty  mat- 
ters, from  which  they  may  be  freed  by  means  of  alcohol  and  ether. 
The  following,  according  to  MM.  Dumas  and  Cahours,  is  the  com- 
position of  the  azotized  principles  of  wheat,  dried  at  140  centig. 
(284"  F.)* 

Carbon.         Hydrogen.         Azote.       Oxygen,  Uulph.  awt 
fho^piiorus. 

Fibrine 53.2  7.0  16.4  23.4 

Albumen 53.7  7.1  15.7  20.5 

C  iseine  (caseum) 53.5  7.1  16.0  2:^.4 

Glutine 53.3  7.2  15.9  23.6 

Legumine.     Some  vegetables,  particularly  some  seeds,  contain  a 
substance  different  from  any  of  those  just  described.     This  M.  Bra 
oonnjt  was  the  first  to  notice  in  the  seeds  of  the  family  of  the  I^e 
guminosae,  and  it  has  been  since  detected  by  Dumas  and  Cahours  ia 

Dumas  et  Cahours,  Annales  de  Chimie  el  1e  Physique,  p.  390,  3e  s6rl». 


T8 


CHEMICAL    CONSTITUTION    OF    VEGETABLES. 


many  different  seeds.  Legumine,  which  plays  an  important  part  in 
the  nutrition  of  animals,  is  obtained  by  digesting  a  quantity  of  pea 
or  bean  meal,  3x  crushed  peas  or  beans  in  tepid  water  for  two  or 
three  hours ;  the  pulp  is  then  pounded  in  a  mortar,  and  afterwards 
mixed  with  its  own  weight  of  cold  water  ;  after  one  hour's  macera- 
tion it  is  pressed  through  a  cloth.  On  standing,  the  liquid  throws 
down  some  fecula.  Filtration  is  employed  to  have  the  liquor  per- 
fectly clear ;  upon  which  a  quantity  of  acetic  acid  diluted  with  from 
eight  to  ten  times  its  weight  of  water  is  gradually  added,  when  a 
snowy  flocculent  precipitate^  of  legumine  falls.  This  is  collected  in 
a  filter  and  washed  with  water  ;  the  legumine  is  then  treated  with 
alcohol,  dried,  and  pulverized,  preparatory  to  digestion  in  ether,  in 
order  to  free  it  from  fatty  matters. 

Legumine  thus  prepared  has  a  pearly  or  lustrous  appearance.  It 
is  insoluble  in  alcohol  and  ether.  Cold  water  dissolves  it  in  large 
quantity.  On  boiling  the  watery  solution,  legumine  is  coagulated 
and  falls  in  flocculi  analogous  to  those  formed  by  albumen  under  the 
same  circumstances.  Weak  hydrochloric  acid  throws  down  legu- 
mine from  its  watery  solution  like  the  acetic  acid  ;  the  concentrated 
acid,  again,  dissolves  it,  acquiring  a  violet  tint,  a  character  which 
also  belongs  to  albumen  ;  but  that  legumine  is  actually  distinct  from 
albumen  is  proved  by  the  circumstance  of  its  being  precipitated  by 
phosphoric  acid  with  three  atoms  of  water,  which  albumen  is  not. 
The  alkalies  dissolve  legumine  at  common  temperatures. 

COMPOSITION  OF  LEGUMINE,  OBTAINED  FROM  DIFFERENT  SEEDS.* 


Carbon.... 

^< 

II 

Is 

M 

1 

S?2 

.-si 

50.9 

5n.!> 

50.7 

50.8 

50.7 

50.5 

50.5 

.50.7 

Hydrogen.. 

6.7 

6.7 

6.7 

6.7 

6.7 

6.9 

6.7 

6.8 

Azote    .... 

18.8 

18.6 

18.8 

18.6 

18.8 

18.2 

18.2 

17. 6 

Oxygen.... 

23.6 

23.8 

23.8 

23.9 

23.8 

24.4 

24.6 

24.9 

100.0 

100.0 

J  00.0 

100.0 

100.0 

100.0 

100.0 

100.0 

The'W  same  azotized  compounds,  or  substances  differing  but  little 
from  theri,  are  very  probably  those  that  are  now  recognised  as  dis- 
tributed through  the  whole  body  of  every  vegetable.  M.  Payen, 
alter  having  ascertained  the  presence  of  these  substances  in  the 
radicles  and  spongioles,  proved  it  in  nearly  all  the  organs.  The 
examination  was  extended  to  a  great  number  of  species  of  different 
families.  The  ascending  sap  of  a  fig-tree,  {Jicus  carica,)  that  of  the 
lime-tree,  of  the  black  poplar,  of  the  vine,  have  all  yielded  ammoniacal 
vapors  under  the  influence  of  fire ;  so  also  do  the  buds,  the  young 
leaves,  the  stigmas,  the  anthers,  &c.t  Thus,  according  to  M.  Payen, 
the  nutritious  juices  which  ascend  from  the  extremities  of  the  radi- 
cles to  the  terminal  points  of  the  leaves,  carry  an  azotized  principle 

•  Dumas  et  Cahours,  Annaies  de  Chimie  et  de  Physique,  t  vL,  p.  423, 3c  s^rl*. 
t  F&yeot  M^imoire  mr  les  d^veloppemens  des  v^taux,  p.  3& 


QUARTERNARY  OR  AZOTIZED  PRINCIPLES.  79 

which  accumulates  in  all  the  growing  organs,  at  the  same  time  ib.at 
it  is  deposited  within  the  entire  extent  of  the  canals  which  the  sap 
traverses.  It  might,  therefore,  be  supposed  that  in  the  latter  situa 
tion  the  azotized  substance  was  associated  with  matters  of  ternary 
constitution,  so  as  to  form  membranes  and  tissues.  But  from  the 
various  organs  of  the  many  species  studied,  M.  Payen  succeeded  in 
dissolving  out,  by  means  of  alkalies,  and  entirely  eliminating  the 
animalized  substances,  without  causing  the  slightest  rent  or  erosion 
in  the  tissues  perceptible  with  the  microscope ;  whence  it  may 
fairly  be  concluded,  that  if  these  substances  everywhere  and  always 
accompany  the  young  tissues  of  plants,  they  still  form  no  integral 
part  of  them.*  The  animalized  matter  seems  consequently  to  pre- 
serve a  kind  of  independence  with  reference  to  the  organs  which 
secrete,  which  convey,  and  which  contain  it ;  it  preserves  a  sort  of 
mobility  which  allows  of  its  displacement.  And  it  was  in  fact  neces- 
sary that  this  should  be  so ;  for  as  the  period  of  maturity  approaches 
we  see  the  azotized  substance  carried  more  particularly  towards  the 
generative  organs,  and  finally  become  fixed,  as  it  were,  and  accumu- 
lated in  the  seeds.  I  have  had  frequent  occasion  to  satisfy  myself 
that  the  trefoil,  the  red  beet,  the  turnip,  &c.,  contain  much  less 
azote  after  ripening  their  seeds  than  they  did  previously  ;  and  all 
husbandmen  know  that  the  straw  or  refuse  of  plants  that  have  run 
to  seed,  forms  very  indifferent  fodder  for  cattle. 

The  cambium^  that  peculiar  globulo-cellular  matter  which  is  con- 
stantly found  accumulated  where  the  vegetable  is  forming  woody 
tissue,  contains,  according  to  MM.  Mirbel  and  Payen,  the  same 
azotiaed  principle  of  an  animal  nature,  in  conjunction  with  ternary 
substances,  whose  composition,  as  we  shall  presently  see,  is  repre- 
sented nearly  by  carbon  and  water.f  As  the  cellular  tissue  is 
evolved  at  the  expense  of  the  cambium,  the  animalized  matters  show 
a  tendency  t6  quit  the  consolidated  organ.  The  departure  of  these 
matters  at  the  epoch  of  the  growth  of  the  cells,  explains  satisfactorily 
wherefore  the  interiors  of  old  trees  contain  but  a  few  thousandths  of 
azote,  while  all  the  organs  of  recent  formation  always  contain 
several  hundredths.  With  the  assistance  of  chemical  analysis  it  is 
possible  to  follow  the  appearance  and  the  removal  of  the  azotized 
matter ;  thus  in  the  alburnum  and  wood  it  is  observed  to  diminish  in 
quantity  from  the  circumference  to  the  centre  ;  this  diminution  is 
also  observed  in  the  branches,  proceeding  from  their  extremities  ta 
their  point  of  junction  with  the  trunk. 

*  Payen,  M6inoire  sur  les  d6veloppemens  des  viS'g^taux,  p.  42. 

f  De  Mirbel  et  Payen,  Comptes  rendus  de  TAcad^uiie  des  Science.s,  t  Kri.  p.  98L 


f 


CHEMICAL  CONSTITXTTION  OF  VEGETABLES. 


§  II.— PROXIMATE  PRINl  iPLES  WITH  A  TERNARY  COM. 
POSITION. 

OF    STARCH. 

Starch  is  contained  in  the  cells  of  vegetables  under  the  form  of 
small  white  granules  which  have  no  crystalline  structure. 

In  the  year  1716,  Leuwenhoeck  ascertained  that  these  granules 
were  globular  bodies  more  or  less  regular  in  their  contours.  He 
believed  that  he  could  perceive  each  globule  enclosed  in  an  envelope, 
a  kind  of  sac  different  in  its  nature  from  the  matter  which  it  con- 
tained. M.  Raspail,  a  few  years  ago,  confirmed  by  his  own  re- 
searches the  observations  of  Leuwenhoeck ;  he  further  attempted 
to  measure  the  diameter  of  the  globules  in  different  kinds  of  starch, 
and  came  to  the  conclusion  that  their  capsule  is  insoluble,  and  that 
it  is  the  internal  part  alone  which  is  soluble  in  hot  water.*  Since 
then  MM.  Payen  and  Persoz  have  ascertained  that  if  the  globules 
of  starch  be  really  surrounded  by  a  capsule,  it  must  he  present  in  a 
quantity  scarcely  appreciable — a  quantity  not  exceeding  joVo^h  of 
the  weight  of  the  starch.  Tiiese  first  researches  were  followed 
by  the  subsequent  observations  of  M.  Payen,  who  has  devoted  him- 
self to  the  study  of  the  amylaceous  principle  with  a  zeal  and  perse- 
verance which  must  secure  him  the  gratitude  of  chemists  and  physi- 
ologists. 

M.  Payen  has  examined  a  vast  number  of  fceculae  microscopi- 
cally ;  the  largest  granules  he  observed  were  obtained  from  one  of 
the  varieties  of  potato,  from  the  menispermum  palmatum,  and  the 
carina  gigantea. 

The  globules  of  starch  frequently  exhibit  a  polyhedral  appearance, 
a  figure  which  evidently  results  from  their  mutual  pressure  as  they 
have  lain  in  the  cells  of  the  vegetable.  Notwithstanding  a  great 
general  analogy  of  form,  the  granules  of  the  starch  of  different 
species  of  vegetables  sfill  present  peculiar  physiognomies,  so  that 
they  can  be  distinguished  in  many  instances  by  the  practised  eye. 
A  character  common  to  the  majority  of  foeculae,  however,  is  round- 
ness of  contour,  when  their  panicles  have  not  been  compressed  by 
their  contact  in  contiguous  cells. 

Microscopical  and  chemical  researches  alike  show  that  starch  is 
homogeneous  in  properties,  as  in  composition  ;  that  its  globules  are 
composed  of  concentric  layers,  the  external  of  which  have  exactly 
the  same  characters  as  the  internal  layers. f  In  the  natural  state, 
starch  is  insoluble  in  water  and  in  alcohol  ;  it  is  very  ductile,  and 
under  the  influence  of  certain  agents  it  exhibits  a  great  degree  of 
contractility. 

Feculas  retain  water  with  considerable  force  ;  the  quantity  re- 


In  1812,  Villars,  in  a  paper  on  the  structure  of  the  potato,  had  already  eitiinated 
the  volume  of  the  globules  of  different  kinds  of  starch, 
t  Frit2xhe,  Aaniles  de  Poggendoif;  t.  ti^^.  p.  jsa. 


I 


TEBNARY  PRINCll'LES STARCH.  81 

tained  varies  with  the  temperature  at  which  the  drying  was  accom- 
plished. Thus  the  feeuhi  of  the  potato,  which  is  moist  and  porous, 
even  when  subjected  to  strong  pressure,  still  retains  45  per  cent,  of 
water.  This  is  the  green  or  raw  starch  of  manufacturers.  Dry 
starch  is  very  hygrometric.  If  after  being  dried  it  is  placed  in  an 
atmosphere  saturated  with  moisture,  at  20°  centig.  (68°  Fahr.)  it 
will  absorb  nearly  36  per  cent,  of  water,  and  its  hulk  increases  in 
the  ratio  of  one  to  one  and  a  half;  in  this  state  starch  is  brilliantly 
white,  and  its  grains  adhere  so  closely  that  they  foim  a  mass  of 
sufficient  firmness  to  take  the  impress  of  a  seal ;  starch  in  this  state, 
however,  pressed  upon  paper  yields  no  perceptible  trace  of  moisture ; 
it  is  too  hard  and  adherent  to  pass  through  a  sieve  ;  and  when 
thrown  on  a  metal  plate  heated  to  125°  (257°  Fahr.)  its  particles  im- 
mediately unite  and  form  a  cake.  The  starch  of  commerce,  in  the 
state  in  which  it  is  usually  found  in  shops,  contains  18  per  cent,  of 
water ;  it  is  either  pulverulent  or  readily  reducible  to  powder, 
though  by  slight  pressure  in  the  hand,  it  may  be  formed  into  a  mass 
or  ball.  After  drying  in  vacuo  at  the  ordinary  temperature,  starch 
retains  no  more  than  10  per  cent,  of  moisture ;  a  temperature  not 
less  than  140"  (284°  Fahr)  is  required  to  dry  it  completely  ;  the 
water  which  it  retains  at  this  temperature  belongs  to  its  constitu- 
tion, and  cannot  be  taken  from  itexcept  by  combining  it  with  bases.* 

MM.  Collin  and  Gaultier  de  Claubry  discovered  the  important 
character  of  starch,  that  of  yielding  a  fine  blue  or  violet  color  on 
combining  with  iodine. f  According  to  M.  Payen,  the  color  is  more 
intense,  nearer  to  blue  and  more  lasting,  in  proportion  as  the  starch 
is  more  strongly  compressed ;  the  effect  of  separation  is  to  turn  the 
blue  to  shades  of  violet  which  approach  redness  as  the  substance  is 
looser.  The  same  fecula,  according  to  the  degree  of  its  aggregation 
in  plants,  is  seen  to  assume  shades,  which  are  first  reddish,  then 
violet,  and  eventually  of  a  more  decided  blue  color,  under  the  action 
of  iodine. J 

M.  Lassaigne  has  noticed  a  very  curious  property  of  the  combina- 
tion of  iodine  and  starch  :  if  an  amylaceous  fluid,  having  the  decided 
blue  color,  be  heated  to  89°  or  90="  C.  (193°  or  194°  Fahr.)  the  solu- 
tion becomes  completely  blanched  ;  but  it  resumes  its  former  tint  as 
the  liquid  cools.^ 

This  property  which  starch  possesses  of  striking  a  blue  color  with 
iodine,  renders  one  of  these  bodies  an  excellent  test  for  the  other. 
However,  as  the  iodine  must  exist  in  the  free  state  to  produce  its 
effect,  it  is  necessary,  when  the  blue  color  does  not  show  itself  at 
once,  in  a  solution  in  which  iodine  is  suspected,  and  to  which  starch 
has  been  added,  to  add  a  few  drops  of  sulphuric  acid,  so  as  to  decom- 
pose the  hydriodic  acid  in  cases  where  it  may  exist. 

It  is  familiarly  known  that  if  raw  starch  be  mixed  with  boiling 
water,  the  result  will  be  a  thick,  paste-made  starch.     According  to 

•  Payen,  W6moire  citt,  p.  88. 

t  Collin  et  GaiUhier  de  Claubry,  Annales  de  Chimie,  t.  xc.  p.  S8 

i  Payen,  M6moire  cite,  p.  105. 

i  Lassaigne,  JoiiraaKde  Chimie  M^dicale,  t  ix.  p.  51Q. 


82  CHEMICAL  CONSTITUTION  OF  VEGETABLES. 

M.  Payen,  the  change  tliat  takes  place  in  the  state  of  the  fecula  it 
owing  to  a  swelling,  a  rupture,  or  disgregation  of  its  granules.  By 
heating  a  drachm  cf  starch,  mixed  with  about  a  couple  of  ounces  of 
water,  to  about  00°  cent.  (140°  Fahr.)  the  microscope  shows  us  that 
the  smallest  or  youngest  gVains — those  possessed  of  the  least  cohe- 
sion— have  absorbed  a  considerable  quantity  of  water,  and  that  the 
expansion  of  the  contents  has  caused  a  certain  number  of  the  glo- 
oulds  to  burst ;  at  this  temperature,  however,  some  grains  of  fecula 
are  observed,  which  do  not  appear  to  have  yet  attained  their  maxi- 
mum of  enlargement,  and  whose  contents  consequently  are  not  yet 
diffused  -through  the  liquid  ;  it  is  only  between  72°  and  100°  cent. 
(161.6°  and  212°  Fahr.)  that  the  maximum  of  expansion  becomes 
general,  and  that  the  solution  acquires  its  greatest  consistency.* 

The  remarkable  property  possessed  by  starch  of  making  a  gluti- 
nous solution  or  thick  paste  with  water  under  the  influence  of  heat, 
led  M.  Payen  to  conjecture  that  a  contrary  effect  would  be  produced 
by  lowering  the  temperature — that  the  starch  might  be  recovered  in 
its  original  state  of  distinct  globules  by  suitable  management :  and 
this  he  in  fact  accomplished  by  an  ingenious  procedure.  Starch 
appears  to  suffer  no  actual  change  when  diffused  in  water  by  exposure 
to  a  temperature  of  212°  Fahr.  ;  the  granules  have  only  swollen  to 
about  thirty  times  their  original  dimensions  by  the  imbibition  of  a 
large  quantity  of  water. 

We  have  already  seen  how  starch  may  be  extracted  from  wheat- 
en  flour  ;  this  method,  however,  is  not  the  one  that  is  usually 
followed  to  procure  this  useful  substance,  so  large  a  quantity  of 
which  is  consumed  in  the  arts.  Formerly,  starch  was  universally 
obtained  from  grain, — wheat ;  at  present  the  potato  furnishes  a  still 
larger  quantity  than  grain.  In  the  equatorial  regions  of  South 
America,  starch  is  aoundantly  prepared  from  the  YucOy  (Jatropha 
manihot,)  and  from  several  species  of  palm. 

To  obtain  starch  from  wheat,  the  grain  is  either  coarsely  ground 
and  mixed  with  water  in  large  tubs ;  or  it  is  put  to  steep  in  sacks 
until  it  is  so  soft  that  a  process  of  kneading  sufiices  to  set  the  starch 
at  liberty. 

Starch  from  potatoes.  The  potatoes  are  grated  after  having  been 
well  washed,  and  the  palp  being  thrown  on  a  sieve,  the  starch  is 
carried  off  by  the  water  and  deposited  in  suitable  vessels.  The 
washings  in  the  manufacture  of  potato  starch  soon  become  putrid 
by  reason  of  the  azotized  matter  which  they  contain,  and  until  lately 
occasioned  much  annoyance,  until  M.  Dailly  conceived  the  happy 
idea  of  turning  them  to  account  as  liquid  manure. 

Starch  of  the  Yvca,  or  Jatropha  manihot.  The  manihot  yields 
very  large  foots,  rich  in  starch.  These  are  taken  tip  a  little  after 
the  flowering,  when  the  fecula  is  most  abundant.  To  extract  the 
starch,  precisely  the  same  process  is  employed  as  in  the  case  of  the 
potato.  In  South  America  the  manioc  is  distinguished  into  yuca 
duke  (mild)  and  yuca  brava,  (malignant ;)  the  latter  epithet  applying 

•  Payen,  M^r.oire  cit  p  96. 


TKRNARY    PRINCIPLES STARCH.  88 

to  the  jatropha  containing  poisonous  juice.  The  two  yucas  are, 
however,  but  one  and  the  same  species ;  at  least  a  skilful  botanist, 
M.  Goudot,  who  resided  for  several  years  in  America,  could  not 
perceive  any  specific  differences  between  them.  The  poisonous 
principle  of  the  yuca  brava  must  be  very  volatile,  or  readily  destroy- 
ed by  heat,  for  the  root  may  be  eaten  with  impunity  after  it  has 
Deen  roasted,  while  the  animals  who  eat  it  in  the  raw  state  soon  ex- 
perience the  most  distressing  effects. 

The  Indians  seldom  prepare  starch  from  the  jatropha ;  but  the 
root  frequently  constitutes  the  staple  of  their  food.  It  is  from  the 
yvca  brava  that  they  obtain  the  cassava,,  which  supplies  the  place  of 
bread  with  them.  Among  the  Indians  in  the  country  near  the  river 
Malta,  one  of  the  principal  tributaries  of  the  Oronoko,  I  have  seen 
the  cassava  prepared  in  the  following  manner  :  the  roots  of  the 
manioc  were  scraped  on  a  sort  of  rasp  formed  of  small  fragments  of 
flint  stuck  into  a  plank  ;  the  pulp  was  then  put  to  drain  in  a  long 
strainer  made  of  the  entire  bark  of  a  species  of  fig  ;  the  juice  having 
drained  away,  water  was  added  to  finish  the  washing ;  the  liquid 
came  out  nearly  clear  and  without  bringing  away  any  perceptible 
quantity  of  starch.  To  form  the  pulp  into  cakes  of  cassava,  it  was 
spread  out  on  an  earthen  dish  placed  over  the  fire ;  the  process  was 
complete  when  the  cassava  was  dry,  and  slightly  toasted  on  the  out- 
side. Cassava  bread  is  not  very  palatable,  but  it  possesses  the  pro- 
perty of  keeping  for  a  long  time  in  spite  of  heat  and  moisture,  and  is 
frequently  an  indispensable  article  of  provision  with  the  South  Amer- 
ican traveller.  The  Indians  say  that  they  cannot  obtain  cassava 
from  the  yuca  dulce. 

Starch  from  pabns.  In  the  Moluccas  and  Philippine  Islands, 
and  in  the  plains  of  Apure,  there  are  certain  palms  which  yield  a 
species  of  fecula.  This  fecula  is  found  in  a  soft  substance,  general- 
ly situated  in  the  centre  of  these  trees.  The  marrow  of  these  palms 
is  dried,  and  when  sifted  presents  itself  in  the  form  of  grains,  which 
in  commerce  bear  the  name  of  sago. 

None  of  the  amylaceous  principles  or  feculas  obtained  by  the 
processes  which  I  have  mentioned  are  absolutely  pure  ;  even  sup- 
posing all  the  soluble  substances  to  have  been  removed  by  washing, 
they  still  retain  fatty  matters,  azotized  principles,  and  coloring 
substances.  Starch  is  purified  by  following  up  the  water  washings 
by  the  action  of  alcohol,  of  acetic  acid,  and  of  ammonia.  Starch  in 
its  state  of  greatest  purity,  and  dried  at  100°  cent.  (212"  Fahr.) 
contains,  according  to  the  analysis  of  M.  Jacquelain  : 

Carbon 44.9 

Hydrogen 6'3 

Oxygen •  48.8 

100.0* 

By  slight  roasting,  amylaceous  feculas  undergo  considerable 
changes  ;  they  become  soluble  in  water,  and  then  present  the  pro- 
perties of  gura.f    Starch  thus  roasted,  supplies  the  place  of  gtra  ia 

•  Jacquelain,  Annales  de  Chimie  et  de  Physique,  t.  Ixiiii.  p.  181,  2e  »6rie. 
f  Vaoquelin  and  Booillun  Lagrange,  Bulletin  de  Phnrmacio,  t.  ill.  p.  54. 


84  CHEMICAL  CONSTITUTION  OF  VEGETABLES. 

various  manufacturing  processes  ;  still  it  si  juld  not  be  confounded 
with  gum  in  a  cliemical  point  of  view.  The  acids  act  with  more  or 
less  energy  on  starch,  and  give  rise  to  different  products.  Nitrie 
acid,  when  it  is  diluted  with  water,  merely  dissolves  fecula;  but  at 
a  certain  degree  of  concentration  it  exerts  a  destructive  action.  In 
this  reaction  several  acids  are  formed,  among  others  oxalic  acid 
By  employing  very  dilute  sulphuric  acid,  Kirchhoff  succeeded  i& 
changing  starch  into  a  saccharine  substance  similar  to  the  sugar  of 
the  grape.  The  operation  may  be  performed  in  a  leaden  or  silvei 
pan,  or,  what  is  preferable,  especially  when  the  process  is  carried 
on  upon  the  great  scale,  in  wooden  vessels,  in  which  the  liquid  mass 
is  heated  by  steam.  According  to  M.  Couverchel,  several  organic 
acids  are  capable  of  changing  fecula  into  sugar  in  a  similar  manner ; 
such  are  oxalic,  tartaric,  and  malic  acids. 

The  artificial  conversion  of  starch  into  grape-sugar  has  not  yel 
been  satisfactorily  accounted  for.  The  acid  employed  does  not  seero 
to  undergo  any  change  :  it  is  found  in  its  original  state  and  quantity 
after  the  operation.  M.  de  Saussure  thinks  that  the  effect  of  the 
reaction  is  the  fixation  of  water  ;  thus  100  parts  of  fecula  yielded 
him  110.40  parts  of  sugar.* 

M.  Couverchel  and  M.  Guerin,  on  the  contrary,  state  that  the 
quantity  of  sugar  obtained  was  less  than  that  of  the  starch  they 
employed. 

Ghnen  exerts  a  reaction  on  starch  similar  to  that  produced  by 
acids  ;  Kirchhoff  discovered,  that  under  the  influence  of  the  azotized 
matters  which  are  met  with  in  flour,  the  fecula  is  converted  into 
sugar. t  Two  parts  of  starch  being  mixed  with  four  parts  of  cold 
water,  on  adding  twenty  parts  of  boiling  water,  a  thick  paste  is  pro- 
duced ;  if  into  this  one  part  of  dry  powdered  gluten  be  introduced, 
and  the  mixture  be  kept  at  the  temperature  of  60°  cent.  (140°  Fahr.) 
the  paste  becomes  more  and  more  liquid,  so  that  the  mixture  may 
be  filtered  at  the  end  of  from  six  to  eight  hours.  By  concentration 
a  sirup  is  obtained,  in  which  small  crystals  of  sugar  are  perceived. 
It  is  well  known  that  during  the  act  of  germination,  fermentable 
saccharine  matter  is  produced.  Kirchhoff  concluded,  from  his  ex- 
periments, that  this  production  of  sugar  in  germination  is  attributa- 
ble to  the  reaction  of  the  gluten  on  the  starch.  Germinating  grain, 
barley-malt,  for  instance,  reacts  rapidly  and  powerfully  on  any  fe- 
cula with  which  it  is  brought  into  contact ;  a  fact  well  known  to, 
and  constantly  taken  advantage  of,  by  manufacturers  of  spirits  from 
potatoes  and  raw  grain,  large  mashes  of  which  are  rapidly  converted 
into  sweet  fermentable  liquids  under  the  action  of  a  little  malt. 

These  facts,  it  is  evident,  cannot  be  explained  by  Kirchhoff's  ex- 
periment ;  in  the  fermentation  of  the  potato,  the  mass  of  fecula  to  be 
converted  into  sugar  is  too  great  compared  with  the  quantity  of  glu- 
ten which  exists  in  the  malted  barley.  Further,  the  gluten  in  grain 
which  has  not  germinated,  scarcely  exerts  any  appreciable  action. 

•  Sausiure,  Bibliothequc  britannique,  t.  Ivi.  p.  333. 
t  Kirchhoff,  JQUTna!  du  Pharinacie,  t.  ii.  p.  2ja 


DIASTASE.  85 

The  principle  which,  in  the  preceding  operations,  converts  the  starch 
into  sugar,  must  therefore  become  developed  daring  germination. 
This  important  point  in  the  art  of  the  distiller  has  been  investigated 
with  great  ingenuity  by  M.  Dubrunfaut  ;*  and  MM.  Persoz  and 
Payen  succeeded  in  separating  the  peculiar  matter  in  barley-malt 
which  possesses  the  property  of  converting  starch  into  sugar.  This 
matter  has  been  called  diastase. 

Diastase  exists  in  the  seeds  of  all  the  cereals  which  have  germi- 
nated ;  it  is  met  with  more  especially  near  the  germs,  it  seems  even 
that  the  radicles  contain  none  of  it.  Nor  is  diastase  observed  in  the 
shoots  or  roots  of  the  potato  ;  it  is  to  be  met  with  only  in  the  tubers, 
around  the  eyes  or  points  where  the  young  sprouts  are  developed, 
precisely  as  M.  Payen  has  remarked,  in  the  place  where  we  should 
conceive  its  presence  to  be  necessary  for  effecting  the  solution  of 
the  fecula.  It  is  also  found  to  exist  in  the  bark  and  beneath  the 
buds  of  trees,  always  in  contact  with  starch. f  Diastase  is  gene- 
rally obtained  from  malt,  and  when  carefully  prepared,  its  peculiar 
power  is  such,  that  one  part  by  weight  is  sufficient  completely  to 
liquefy  two  thousand  parts  of  starch.  Diastase  is  solid,  white,  amor- 
phous, insoluble  in  pure  alcohol,  soluble  in  water  and  weak  alcohol 
The  solution  very  readily  undergoes  change ;  it  becomes  acid,  and 
then  no  longer  exerts  any  action  on  fecula.  When  dried,  it  keeps 
much  better ;  still,  at  the  end  of  two  years,  it  seems  to  have  lost  its 
distinguishing  properties.  Diastase  has  no  action  on  vegetable  tinc- 
tures, on  albumen,  gluten,  cane-sugar,  gum-arabic,  or  the  woody 
fibre.  That  which  more  especially  characterizes  it,  is  its  powerful 
action  on  fecula ;  it  may  be  advantageously  used  to  separate  and 
purify  the  preceding  substances,  when  they  are-  mixed  with  starch. 
The  presence  of  diastase  in  malt  explains  the  phenomenon  of  the 
liquefaction  of  starch  effected  by  the  action  of  a  small  quantity  of 
that  substance.  This  solution  is  not  effected  by  gluten,  nor  by  hor- 
deine,  as  M.  Dubrunfaut  had  imagined. 

By  the  action  of  diastase,  or  of  malted  barley,  the  starch  on  being 
liquefied  is  not  entirely  converted  into  sugar  ;  there  are  other  dis- 
tinct products  to  be  considered  in  this  change.  The  sirup  ob- 
tained by  concentrating  the  liquefied  starch,  contains  sugar  capable 
of  undergoing  the  vinous  fermentation,  and  a  gummy  matter,  dextrine. 
These  two  substances  may  be  separated  by  means  of  dilute  alcohol, 
which  dissolves  the  sugar  and  leaves  the  gum  untouched.  The 
relative  quantities  of  dextrine  and  sugar  produced  by  the  action  of 
diastase  are  variable,  and  depend  both  on  the  temperature  at  which 
the  process  is  conducted,  and  on  the  continuance  of  the  reaction 
In  tlie  first  period  of  the  process,  the  dextrine  predominates ;  but  it 
becomes  less  and  less  by  degrees,  and  finally  gives  place  to  sugar. 

M.  Guerin  ascertained  a  curious  fact,  which  shows  how  the  dias- 
tase developed  in  plants  may  act  on  their  starch  :  reaction  takes 
place  even  at  ordinary  temperatures.     In  one  of  M.  Guerin's  experi- 

*  Dubrunfaut,  M6moires  de  la  Soci6t6  Royale  d' Agriculture,  annee  1823,  p.  ^40. 
t  Payen  and  Persoz,  Annales  de  Chiinie  et  de  Physique,  t.  liii.  p.  Ti '  t.  Ivi.  p.  337 
9e  sirie. 

8 


BO  f'HEMlCAL  CONSTITUTION  OF  VEGETABLES. 

ments,  at  a  temperature  no  higher  than  20°  cent.  (68°  Fahr.)  a  quan- 
tity of  starch,  at  the  end  of  twenty-four  hours,  was  converted  into 
sirup,  which  yielded  77  per  cent,  of  saccharine  matter.* 

Pure  dextrine.  M.  Payen  freed  dextrine  from  the  sugar  which 
usually  accompanies  it  by  precipitating  a  sirup  of  fecula  previously 
dissolved  in  dilute  alcohol,  by  means  of  alcohol  nearly  free  from  wa- 
ter. Dextrine  well  dried,  and  reduced  to  powder,  has  a  specific 
gravity  of  1.51.  The  specific  gravity  of  pure  starch  is  1.51,  that  ol 
the  sugar  of  starch  1.61.t 

M.  Payen  found  dextrine  dried  at  a  temperature  of  212°  Fahr.  to 
consist  of — 

Carbon 44.3 

H  y  d  rogen 6.0 

Oxygen 49.7 

100.0t 

a  composition  identical  with  that  of  starch. 

We  have  seen  that  water,  acidulated  with  sulphuric  acid,  trans- 
forms starch  into  sugar ;  and  that  in  this  respect,  the  acid  acts  pre- 
cisely in  the  same  way  as  malted  barley,  like  which,  the  acid  first 
causes  the  fecula  to  pass  into  the  state  of  dextrine  :  by  checking  the 
reaction  at  the  proper  moment,  this  substance  may  thus  be  obtained, 
as  was  shown  by  Messrs.  Biot  and  Persoz.^  When  starch,  for  in- 
stance, is  triturated  with  concentrated  sulphuric  acid,  if  the  mixture 
be  diluted  with  half  its  volume  of  water,  and  be  left  at  rest  for  an 
hour,  alcohol  will  throw  down  almost  the  whole  of  the  starch  employ- 
ed in  the  state  of  dextrine. 

M.  Payen  has  remarked  that  starch  is  never  met  with  in  the  vege- 
table tissues  while  in  the  rudimentary  state  ;  the  spongioles,  the  radi- 
cles, the  foliaceous  buds,  the  interior  of  the  ovules,  contain  none  of  it. 
Nor  is  starch  found  in  the  epidermis,  nor  in  the  primary  cells  of  the 
subjacent  tissues.  This  proximate  principle  seems  to  be  exclu- 
ded from  those  parts  of  vegetables  that  are  more  directly  exposed  to 
atmospheric  influences  :  it  is  only  met  at  a  certain  depth ;  and  the 
globules  which  constitute  starch  increase  in  number  and  in  size  in 
the  cells  most  remote  from  the  surface.  The  subterraneous  organs 
of  plants, — certain  bulbs,  most  tubers,  abound  in  amylaceous  matter. 
It  might  be  maintained  that  light  modified  this  substance,  at  the  very 
moment  that  it  was  subjected  to  the  vital  influence,  and  that  it  was 
only  preserved  in  the  dark. 

On  the  globules  of  some  species  of  fcEcula  there  is  found  a  point 
or  hilum,  which,  according  to  some  observers,  serves  to  fix  them  to 
the  parietes  of  the  cells  which  enclose  them.  It  often  happens, 
nowever,  that  no  hilum  can  be  distinguished,  even  by  the  help  of  the 
most  powerful  microscopes;  to  render  it  apparent,  recourse  must  be 
had  to  desiccation,  which,  by  causing  the  globular  mass  to  shrink, 
allows  the  part  carrying   the  hilum   to  project,  by  reason  of  its 

•  Gu^rin,  Annates  de  Chlmle,  t.  Ix.  p.  42,  3e  86rie. 

i  Payen,  M6moires  cit6s,  p.  169.  %  Idem,  p.  157 

Biot  and  Tersoz,  Annates  de  Chimie  et  de  Physique,  t.  lii.  p.  73,  ~ 


INULINB.  87 

•tronger  cohesion.  M.  Payen  does  not  regard  the  hilum  as  a  point 
of  permanent  attachment,  connecting  the  grain  of  starch  to  the  in- 
terior wall  of  the  cell.  He  considers  it  as  the  orifice  of  the  duct  by 
wiiich  growth  is  effected  by  intersusception.  In  support  of  this 
view,  M.  Payen  observes,  that  in  a  great  number  of  vegetable  cells, 
especially  in  those  of  the  potato,  and  of  the  rhizomas,  the  globules 
of  starch  are  developed  in  such  quantity,  that  it  is  actually  impossi- 
ble that  each  of  these  should  be  united  directly  to  the  inner  wall  of 
the  cell.* 

INULINE. 

This  substance,  discovered  by  Rose  in  the  Inula  helenium,  pre- 
sents certain  analogies  with  starch.  It  forms  the  greater  part  of 
the  solid  matter  of  the  tubers  of  the  Jerusalem  Artichoke  and 
Dahlia,  which  do  not  contain  starch.  Inuline  is  dissolved  in  boiling 
water ;  on  cooling  it  is  deposited  in  globules,  which,  under  the 
microscope,  appear  diaphanous,  adhering  to  one  another  like  strings 
of  beads ;  exposed  to  a  temperature  of  367°  Fahr.  it  melts  com- 
pletely and  acquires  new  properties,  becoming  soluble  in  cold  water 
and  in  alcohol.  Inuline  is  transformed  into  dextrine  and  sugar  by 
the  mineral  acids ;  but  it  possesses  certain  properties  which  show 
it  distinct  from  true  starch.  In  the  first  place,  it  is  not  colored  by 
iodine ;  and  then  acetic  acid,  which  is  without  action  on  starch, 
produces  with  inuline  precisely  the  same  effects  as  the  sulphuric, 
phosphoric,  and  hydrochloric  acids  ;  finally,  diastase,  whose  reaction 
upon  starch  is  so  peculiar,  so  prompt,  and  so  powerful,  does  not 
cause  any  change  in  inuline.  It  is  therefore  easy  to  separate  these 
two  substances  when  they  are  mingled,  by  treating  the  mixture 
either  with  acetic  acid,  which  dissolves  the  inuline,  or  with  diastase, 
which  liquefies  the  starch.  Inuline  has  been  analyzed  by  M.  Payen, 
after  having  been  dried  at  253°  Fahr.  and  having  been  melted  at 
367°  Fahr.     In  both  cases  it  has  the  same  composition. 

Carbon 46.6 

Hydrogen 6.1 

Oxygen 493 

100.0 

The  composition  here  is  obviously  the  same  as  that  of  starch  and 
dextrine. 

OF    WOODY    MATTER    AND    CELLULAR   TISSUE. 

The  most  solid  part  of  plants,  thai  which  forms  in  some  sort  theb 
skeleton,  is  the  wood  in  trees,  the  woody  fibre  in  herbaceous  plants. 
Woody  fibre,  as  it  used  to  be  prepared  and  considered,  viz.  by  the 
reaction  of  certain  agents  which  have  the  property  of  dissolving  the 
gummy,  resinous,  and  saline  substances  which  are  commonly  asso- 
ciated vi'ith  it,  consists,  in  fact,  of  two  substances,  one  the  cellular 
substance,  constituting  the  tissue  of  wood  and  of  all  the  organs  of 

♦  Payen,  M6molres  cit6s,  p.  183. 


88 


CHEMICAL   COXSTmrriON   OF    VEGETABLES. 


plants,  the  other  the  woody  substance,  properly  so  called,  filling, 
and  in  some  sort  consolidating  the  cells.  This  distinction  between 
these  two  elements  of  wood  was  first  made  by  M.  Mohl ;  but  M. 
Payen  was  the  first  who  fixed  the  opinion  of  chemists  and  of  vege- 
table physiologists  upon  the  true  nature  of  these  immediate  princi- 
ples.* By  treating  the  vegetable  tissue  in  its  nascent  and  stili 
gelatinous  state — the  unimpregnated  kernel  of  the  almond,  of  the 
apricot  tree,  &c.,  the  membranous  matter  of  the  cambium  of  the 
cucumber,  the  spongioles  of  radicles,  leaves,  wood,  &c. — with  differ- 
ent menstrua,  M.  Payen  obtained  the  cellular  tissue  in  the  state  of 
purity,  and  having  an  elementary  composition  almost  identical,  from 
whatever  source  derired  ;  a  fact  which  may  be  seen  from  the  fol- 
lowing table,  which  gives  the  composition  of  cellular  tissue  from 
different  sources  after  having  been  dried  at  352°  Fahr. 


Carbon. 

Hydrogen. 

Oxygen. 

Ovules  of  the  almond-tree     . 

43.6 

6.1 

50.3 

'*      of  the  apple  and  pear 

44.7 

6.1 

49.2 

"      of  the  helianthus  annuus   . 

44.1 

6.2 

49.7 

Pith  of  the  elder 

43.4 

6.0 

50.6 

Cotton 

44.4 

6.1 

49.5 

Endive 

43.4 

6.1 

50.5 

Banana          ...                  .         . 

43.2 

6.5 

50.3 

Leaves  of  the  asrave       .... 

44.7 

6.4 

48.9 

Cotton  of  the  Virginian  poplar 

44.1 

6.5 

49.4 

Heart  of  oak 

44.5 

6.0 

49.5 

Pine-tree 

44.4 

7.0 

48.6 

Peri  sperm  of  the  phytelaphas 

44.1 

6.3 

49.6 

Mushroom 

44.5 

6.7 

48.8 

The  primary  tissue,  consequently,  which  constitutes  the  skeleton 
of  wood,  is  still  isomeric  or  identical  in  elementary  composition  with 
starch.  With  mineral  acids  the  cellular  tissue  further  undergoes 
changes  which  assimilate  it  with  starch  ;  for  on  treating  it  with  sul- 
phuric, acid  it  is  changed  into  dextrine  and  sugar. 

The  composition  of  the  cellular  tissue  differs  considerably  from 
that  of  the  woody  fibre  as  it  has  hitherto  been  obtained  after  the 
action  of  solvents,  and  been  examined  by  preceding  chemists. 
Pure  wood  or  woody  tissue  consists  of  the  following  proportions  of 
eie.nients : 


*  Dtunas,  Compte*  rendos,  vol.  viii.  p.  53. 


WOOD. 


89 


1 
1 

X 

c 

Authorities. 

\Vo:,dy  tissue  of  the  oak 

41.8 

5.7 

52.5 

Gay-Lussac  and  Thenard. 

"                of  the  beech 

42.1 

5.8 

51.5 

<«                          « 

"               of  the  box 

44.4 

5.6 

50.0 

Prout. 

«               of  the  willow 

44.6 

5.6 

49.8 

(( 

"               of  the  oak 

49.7 

6.0 

44.3 

(( 

"               of  the  beech 

44.3 

6.0 

49.7 

Payen. 

"               of  the  aspen 

44.5 

6.1 

49.4 

<t 

Wood  in  the  natural  state : 

45.6 

6.4 

48.0 

(( 

"     of  the  oak 

39.4 

6.2 

54.4 

K 

"     of  the  beech 

39.3 

6.3 

54.4 

(( 

"     of  the  herminiera 

46.9 

5.3 

47.2 

{( 

From  these  analyses  it  appears  that  wood  in  the  natural  state 
contains  more  carbon  than  woody  tissue  obtained  in  the  way  of  puri- 
fication, and  that  this  latter  substance  is  also  richer  in  carbon  than 
the  cellular  tissue  which  necessarily  forms  part  of  it.  In  the 
purified  woody  tissue,  therefore,  the  cellular  tissue  is  associated  with 
the  principle  which  fills  its  cells,  or  which  incrusls  it,  and  it  is 
to  this  matter  that  M.  Payen  has  applied  the  name  of  incrusting 
matter ;  it  is  wood  properly  so  called  ;  it  is  that  which  gives  to 
wood  its  hardness,  its  tenacity  ;  it  predominates  in  hard  wood  and  in 
knots  ;  it  corresponds  with  the  duramen  of  physiologists  ;  it  consti- 
tutes almost  the  whole  of  the  hard  particles  which  are  met  with  in 
woody  pears  and  in  cork,  and  which  are  hard  enough  to  blunt  well- 
tempered  steel  instruments.  As  this  incrusting  matter  is  friable,  in 
many  instances  it  may  be  pulverized  and  separated  from  the  tissue 
which  surrounds  it,  this  last  tearing  or  yielding  in  shreds  under  the 
pestle.  By  means  of  the  sieve  the  incrusting  matter  may  in  this 
simple  way  be  obtained  nearly  in  a  state  of  purity.  The  analysis 
of  M.  Payen  shows  it  to  consist  of : — 

Carbon 53.8 

Hydrogen 6.0 

Oxygen 40.2 

100.0 

Deducting  resinous  matters  susceptible  of  solution  in  alcohol  or 
ether,  and  of  gummy  and  other  substances  which  are  soluble  in  water, 
the  tissues  of  vegetables  must  consequently  possess  an  elemeiitary 
composition  which  varies  between  that  of  the  cellular  tissue  and 
that  of  the  incrusting  matter ;  these  are  the  extreme  terms,  and  the 
entire  composition  of  the  mixed  tissues  will  be  by  so  much  the  richer- 
in  carbon  as  they  contain  less  cellular  tissue.  The  incrusting  mut- 
ter being  soluble  in  alkaline  leys,  it  was  by  treating  wood  with  solu- 
tions of  soda  and  potash  that  M.  Payen  succeeded  in  obtaining  the 
cellular  tissue,  which  is  much  less  susceptible  of  the  action  of  thesa 

8» 


90  CHEMICAL  CONSTITUTION  OF  VEGETABLES. 

agents.  But  treatment  of  different  kinds,  which  it  is  not  necessary 
to  enter  upon  in  this  place,  is  required  to  procure  the  substance  in  a 
state  of  perfect  purity.* 

The  facts  which  have  just  been  exposed,  in  regard  to  the  chemi- 
cal composition  of  wood,  corroborate  the  observations  of  physiolo- 
gists. We  now  understand  much  better  than  we  did  formerly  the 
changes  which  the  cells  of  vegetables  experience  as  they  grow  and 
become  aged  :  it  is  by  the  appearance  of  the  incrusting  woody  mat- 
ter that  their  walls,  thin,  transparent,  and  colorless  at  first,  get  thick, 
become  opaque,  and  acquire  consistence.  By  means  of  the  dissec- 
tions effected  by  M.  Payen  with  the  aid  of  purely  chemical  means, 
we  may  obtain  assurance  that  the  tissues  of  all  vegetables,  whether 
phoenogamous  or  cryptogamous,  may  be  reduced  to  a  single  substance, 
cellular  tissue,  having  an  invariable  composition,  and  forming  the 
vesicles  or  bladders  of  the  cellular  mass  of  plants. 

This  matter  exists  nearly  in  an  isolated  state  in  the  thick  walls  of 
the  cells  of  the  perisperms  of  various  seeds,  those  of  the  date  for 
example.  From  the  microscopic  researches  of  M.  Payen  and  A. 
Brongniart,  it  appears  that  the  matter  which  is  added  to  the  young 
cells  is  not  deposited  upon  the  inner  surface  of  their  walls,  but  that 
it  penetrates  and  insinuates  itself  into  their  tissue.  The  relation  of 
the  cellular  to  the  woody  matter  in  the  development  of  the  walls  of 
cells  varies  very  much,  some  perisperms  containing  nothing  but  pure 
cellular  tissue,  while  the  stony  concretions  of  the  pear  and  of  cork 
consist  almost  entirely  of  incrusting  woody  matter. 

Wood,  in  the  general  acceptation  of  the  word,  is  the  solid  part  of 
the  trunk  and  branches  ;  the  properties  and  aptitudes  of  the  substance 
vary  greatly,  according  to  the  plant  which  has  produced  it.  Wood 
is  of  higher  density  than  water,  and  if  it  floats  in  this  fluid  it  is  only 
because  of  the  air  with  which  its  pores  are  filled.  Saw-dust,  chips, 
and  larger  pieces  of  wood  sink  when  the  air  which  they  contain  is 
expelled  and  replaced  by  water.  The  specific  gravity  of  the  white 
woods,  such  as  those  of  the  willow  and  pine,  is  about  1.46,  that  of 
the  heaviest  woods,  such  as  those  of  the  oak  and  the  beech,  1.53. 

DENSITY  or  DIFFERENT   KINDS   OF   WOOD  ACCORDINO  TO   BRI8S0N. 


Pomegranate 1.35 

Guaiac,  Ebony 1.33 

Box 1.32 

Oak  of  60  years  old,  the  heart. ..  1.17 

Medlar 0.94 

Olive 0.92 

Spanish  Mulberry  .  0.89 


Orange 0.70 

Quince 0.70 

Elm,  the  trunk 0.67 

Walnut 0.67 

Pear 0.66 

Spanish  Cypress 0.64 

Lime 0.60 


Beech 0.85     i     Hazel 0.60 

Ash 0.84         Willow 0-53 

Hornbeam 0.80         Thuya 0..56 

Yew 0.80     I     Pine 0-55 

Apple 0-79     1     Spanish  white  poplai 0.52 


Plum o.: 

Maple 0.75 

Cherry 0.75 


Pine  0.49 

Poplar 0.38 

Cork 0.24 


*  For  an  account  of  these,  see  Payen  in  proceedings  of  the  Academy  of  Science^ 
voL  viL  p.  1055. 


WOOD.  01 

It  must  not  be  forgotten,  however,  that  age,  climate,  and  soil  ex- 
ert a  marked  influence  upon  the  specific  gravity  of  the  same  species 
of  wood. 

Wood,  according  to  the  use  for  which  it  is  intended,  is  distinguished 
into  fire-wood,  building  timber,  and  dye-wood.  When  first  cut  down, 
all  timber  contains  a  considerable  quantity  of  water ;  100  parts  of 
walnut-tree  dried  at  212"  Fahr.  lost  37.5  parts  by  weight ;  of  white 
oak,  41  parts  ;  of  maple,  48.  On  an  average,  the  quantity  of  water 
contained  in  green  wood  may  be  estimated  at  about  40  per  cent.  ; 
and  drying  or  seasoning  for  eight  or  ten  months  >ill  not  cause  the 
loss  of  more  than  about  25  per  cent  of  water.  The  wood  which  is 
used  for  burning  almost  always  contains  about  a  quarter  of  its  weight 
of  moisture,  which  not  only  does  not  assist  in  producing  heat,  but 
actually  dissipates  a  great  deal  during  its  conversion  into  vapor.  It 
is,  therefore,  highly  advantageous  in  all  operations  where  wood  is 
the  fuel,  only  to  employ  that  which  is  thoroughly  dry.  So  well  is 
this  fact  ascertained,  that  in  some  manufactories  the  wood  is  previ- 
ously dried  in  stoves  before  being  consumed  in  the  furnace. 

The  composition  of  woody  matter  may  be  represented  by  carbon 
and  water  :  of  carbon  the  mean  may  be  stated  at  52,  of  hydrogen 
and  oxygen,  in  the  proportions  which  form  water,  at  48.  The  defi- 
nitive products  of  its  combustion  ought  consequently  to  be  carbonic 
acid  and  water.  The  heat  disengaged  during  this  combustion,  neces- 
sarily proceeds  from  the  union  of  the  combustible  elements  of  the 
wood  with  the  oxygen  of  the  atmosphere.  But  in  this  particular 
case,  the  hydrogen  being  already  present  with  the  proportion  of  oxy- 
gen required  for  its  combustion,  it  may  be  regarded  as  already 
burned,  the  state  of  condensation  in  which  the  oxygen  exists  being 
considered.  The  heat  produced  by  the  wood,  tl>«refore,  depends 
solely  on  the  quantity  of  carbon  which  it  contains. 

Natural  philosophers  in  France  agree  in  designating  as  unity,  in 
reference  to  caloric,  the  quantity  of  heat  necessary  to  raise  a  kilo- 
gramme, or  2.2  lbs.  avoirdupois  of  water,  one  degree  of  the  centi- 
grade thermometer,  (r.8  F.)  The  following  table,  by  Rumford. 
is  intended  to  show  the  different  calorific  or  heating  powers  of  dif- 
ferent kinds  of  wood,  and  its  interpretation  is  this :  since  1  kilo- 
gramme or  2.2  lbs.  avoird.  of  lime-tree  gave  out  3460  units  of  heat, 
it  follows  that  this  quantity  of  the  combustible  would  suffice  to  raise 
by  1  degree  centigrade,  (T.SF.,)  for  example,  from  10°  to  IT  cent. 
3460  kilogrammes,  or  7612  lbs.  avoirdupois  of  water. 


•2 


CHEMICAL  CONSTITUTION  OF  VEGETABLES. 


Kinds  of  wood. 

Units  of  heat 
evolved. 

Lime-tree,  dry 

3460 

The  same,  thoroughly  stove  dried 

3960 

Beech,  dry,  four  years  seasoned 

3375 

The  same,  well  dried  in  a  stove 

3630 

Elm,  from  four  to  five  years  seasoned      . 

3037 

Oalc,  fire-wood 

3550 

Ash,  dry         ...... 

3075 

Wild  cherry  .         . 

3375 

Fir,  dry           .         .                  ... 

3037 

The  same,  well  dried  in  a  stove      . 

3750 

Poplar,  seasoned 

3450 

The  same,  well  dried  in  a  stove 

3712 

Hornbeam 

3187 

Oak,  dry 

3300 

From  the  experiments  of  Clement,  it  appears  that  the  heating 
power  of  charcoal  is  equal  to  7050  units.  Dry  wood  containing,  as 
we  have  seen,  52  per  cent,  of  charcoal,  its  heating  power  has  been 
deduced  theoretically,  as  equal  to  3666.  Mr.  Marcus  Bull  in  Amer- 
ica, made  a  series  of  experiments  to  determine  the  relative  quantities 
of  heat  given  out  by  different  kinds  of  wood,  from  which  M.  Peclet 
has  been  led  to  conclude  that  the  same  weight  of  dry  wood  of  every 
kind  has  the  same  heating  power,  and  that  this  for  a  kilogramme, 
or  2.2  lbs.  avoird.  of  wood  dried  by  artificial  means,  is  equal  to  3500 
units,  while  the  same  quantity  of  the  same  wood  having  been  cut 
and  seasoned  during  from  ten  to  twelve  months,  and  containing  from 
20  to  25  percent,  of  water,  is  no  higher  than  about  260  units. 

By  way  of  comparison,  I  shall  here  add  the  heating  power  of  the 
several  combustibles  in  general  use,  in  contrast  with  that  of  wood  : 

1  kilogrm.  or  2.2  lbs.  avoird.  of  wood-charcoal  produces  7226  units  of  heat. 

"  coal  6000  " 

"  "  peat  3005  " 

"  "  peat  charcoal  6400  " 

Although  the  same  quantities  of  wood,  brought  to  the  same  degree 
of  dryness,  appear  to  have  the  same  absolute  calorific  power,  all  are 
not  alike  adapted  to  the  same  purposes.  Hard  woods  burn  slowly, 
and  give  out  less  heat  in  a  certain  time  than  the  less  compact  kinds 
of  wood.  This  is  the  reason  why  fir  is  preferred  to  oak  in  furnaces 
where  the  object  is  to  obtain  the  most  intense  heats.  It  were  for- 
eign to  our  object  to  enter  upon  any  consideration  of  the  various 
qualities,  or  of  the  adaptation  to  particular  uses,  of  different  species 
of  limber.  I  may,  however,  add  a  table  of  the  ordinary  dimensions 
of  well-grown  trees  of  different  kinda,  such  as  are  cojuixionly  found 
iu  these  countries . 


TREES. 


93 


Trees. 

Usual  height  of 

Usual 

Trunk. 

Diameter. 

Feet. 

Inches. 

The  spruce  fir 

Larch 

26  to   100 

> 

47.1 
39.3 

Poplar 

19  "     65 

31.8 

Pine            .                           ... 

16  «     65 

34.1 

Plane          .         . 

36.1 

Oak,  Elm  .                         ... 

31.4 

Birch          .                 .... 

29.4 

Beech 

-     16  «    48 

28.2 

Lime                    ..... 

25.9 

Ash 

23.5 

Willow 

11.7 

Chestnut     ...                  .         . 

13  "    48 

36.1 

Chestnut  (another  variety) 

28.2 

Maple 

10  «    48 

28.2 

Service 

13  "     39 

17.6 

Acacia 

13  «    26 

19.2 

Hornbeam  . 

i 

21.2 

Mulberry    .... 

•     10  «    23 

16.5 

Wild  Pear 

S 

14.1 

Crab                      .         .         .         . 

6  "     20 

12.9 

Walnut 

6  "     16 

36.1 

These  may  be  taken  as  the  measurement  of  trees  at  their  full 
growth,  and  fit  for  felling.  The  soil  being  of  the  same  quality,  the 
dimensions  of  trees  depend  especially  upon  their  age  ;  individual 
trees  of  the  same  species,  however,  occasionally  acquire  extraor- 
dinary dimensions. 

Every  one  must  have  noticed  the  rapidity  with  which  young  trees 
grow  ;  but  is  the  growth  the  same  for  every  period  of  the  existence 
of  trees,  or  do  they  attain  a  certain  determinate  size  like  animals, 
and  then  cease  from  further  increase  ?  We  have  found  that  in 
those  climates  where  vegetation  is  suspended  for  a  portion  of  the 
year,  the  increase  in  the  diameter  of  trees  takes  place  periodically 
by  the  addition  of  a  concentric  layer  of  woody  tissue  ;  so  that  it  is 
possible  to  determine  the  age  of  a  dicotyledonous  tree  by  the  number 
of  its  concentric  rings,  counted  at  the  bottom  of  the  trunk.  With  a 
view  to  ascertain  the  amount  of  increase  in  the  woody  layers  at  dif- 
ferent periods  of  vegetable  life,  De  Candolle  measured  their  thick- 
ness, and  found  that  if  the  annual  increase  presented  a  certain  re- 
gularity, it  was  still  very  far  from  being  absolute  even  in  the  case 
of  a  single  species.  The  oak  especially  offered  striking  anomalies  ; 
thus  a  trunk  which  had  grown  slowly  in  diameter  was  found  to  have 
increased  more  rapidly  as  it  got  older.  He  found  young  trees  ol 
the  same  species,  the  growth  of  which,  very  slow  at  first,  by  and 
Dy  became  accelerated,  and  then  fell  off  in  a  third  period  of  their 
existence.     From  the  whole  of  his  observations,  De  Candolle  900- 


04  TREES— TIMBER. 

eludes  that  the  growth  of  our  common  European  trees  having  gone 
on  with  a  certain  rapidity  to  the  age  of  from  about  fifty  to  seventy 
years,  then  became  slower,  but  continued  regular  to  extreme  age. 
The  inequalities  of  growth,  conspicuous  in  the  different  thicknesses 
of  different  rings,  he  thinks  are  mainly  due  to  the  kind  of  soil  which 
the  mass  of  the  roots  encountered  in  their  progress,  or  to  the  re- 
moval of  other  trees  which  grew  in  the  vicinity.  The  diminished 
thickness  of  the  rings,  after  trees  have  passed  a  certain  age,  he 
ascribes  to  the  depth  to  which  the  roots  have  now  penetrated,  and 
their  consequent  remoteness  from  the  air  ;  and  further,  to  the  resist- 
ance opposed  to  the  expansion  of  the  trunk  by  the  bark,  which  has 
now  become  thick,  hard,  and  unyielding.  Mr.  Knight  found  that 
old  pear-trees,  relieved  of  their  outer  bark,  formed  more  wood  in  a 
couple  of  summers  afterwards,  than  they  had  made  in  the  twenty 
years  that  preceded  the  operation.* 

The  forests  of  intertropical  countries  produce  a  vast  number  of 
gigantic  trees,  many  of  which  might  doubtless  be  turned  to  excellent 
use  ;  but  the  information  we  have  on  the  trees  of  these  latitudes  is 
very  imperfect.  In  New  Granada,  the  wood  which  is  known  undei 
the  name  of  wood  of  St.  Martha,  {astroneum  graveolens  ?)  is  fre 
quently  employed  for  building  purposes  as  well  as  for  making  furni- 
ture. It  is  very  hard,  and  more  beautiful  than  mahogany,  its  color 
being  deeper.  M.  Goudot  measured  a  tree  of  this  kind,  which  was 
1.6  metre  or  nearly  4^  feet  in  diameter,  including  the  alburnum,  and 
had  32  centimetres  or  upwards  of  18  inches  of  heart- wood.  Belfries 
having  supports  of  this  wood  are  met  with,  which  have  stood  for 
more  than  a  century  exposed  to  all  the  inclemencies  of  the  weather. 
This  tree  grows  in  the  dry  soils  of  the  hottest  regions  of  South 
America,  and  seldom  at  an  elevation  of  more  than  about  fifteen  hun- 
dred feet  above  the  level  of  the  sea. 

Cedar  {cedrela  odorata)  is  never  attacked  by  insects,  doubtless 
because  of  its  aromatic  odor ;  this  valuable  property  makes  it  in- 
valuable as  building  timber.  The  tree  attains  to  large  dimensions. 
M.  Goudot  measured  one  in  the  forest  of  Quindiu  in  South  America, 
which  was  upwards  of  150  feet  in  height  by  more  than  Q\  feet  in 
diameter.  It  grows  freely  through  a  zone  of  considerable  "breadth, 
from  a  height  of  about  3280  to  6560  feet  above  the  level  of  the  sea, 
a  circumstance  which,  according  to  my  own  observations,  would  in- 
dicate the  extreme  temperature  of  the  district  which  it  inhabits  to 
be  between  66°  and  76°  Fahr. 

There  are  several  other  beautiful  and  useful  timber  trees  of  the 
Cordilleras — the  Nogal  {juglans  .  .  .?)  which  grows  between  0500 
and  9800  feeta?bove  the  sea  line  ;  the  escoho,  the  pino  {taxus  montana 
Willd.)  whose  region  lies  between  the  2.800  and  11.400  feet  of  eW- 
vation  ;  the  arayan  and  the  guayacan, — all  are  serviceable  in  one 
direction  or  another.  The  caracoli  {anacardium  caracoli)  and  the 
fig  {Ignerones)  are  trees  which  attain  to  extraordinary  sizes,  and 
ftffoid  light  woods  that  prove  useful  in  various  circumstances.     Uc« 

•  D«  CandoUe,  Veuetablc  Physiology,  p.  975. 


TREES ^TIMBEX.  05 

let  the  tropics,  indeed,  the  trees  generally  exhibit  a  luxuriance  of 
vegetation  which  strikes  European  travellers  with  amazement ;  M. 
Goudot,  for  example,  measured  a  bomhax  (B  pentandrum)  no  more 
than  sixty  years  old,  the  trunk  of  which  was  8  metres  or  26}  feet 
in  circumference,  and  whose  boughs  covered  a  circular  area  of  39 
metres  or  120  feet  in  diameter. 

There  is  a  beautiful  tree  which  grows  in  the  valleys  of  Arragua 
in  Venezuela,  the  Zamang,  a  species  of  mimosa,  according  to  Hum- 
boldt, one  of  whicb,  in  particular,  is  greatly  celebrated,  and  under 
the  shade  of  which  I  rested  on  the  24th  of  January,  1823.  This 
magnificent  tree  is  to  be  distinguished  at  the  distance  of  a  league  ; 
its  branches  form  a  hemispherical  crown  of  187  metres  or  613  feet 
in  circumference,  extending  like  a  vast  umbrella,  the  points  ap- 
proaching to  within  from  10  to  16  or  18  feet  of  the  ground.  The 
trunk  of  this  extraordinary  tree  is  nearly  65  feet  in  height  and  up- 
wards of  9^  feet  in  diameter.  This  tree  is  an  object  of  veneration 
with  the  Indians.  It  does  not  seem  to  have  altered  in  its  appear- 
ance since  it  was  first  particularly  noticed ;  the  earliest  conquerors 
of  Venezuela  seem  to  have  met  with  it  in  the  same  state  as  it  is  at 
the  present  time.  When  Himiboldt  measured  the  Zamang  de  Tur- 
mero,  its  branches  on  one  side  were  entirely  stripped  of  their  leaves. 
Twenty  years  afterwards  1  found  it  green  in  every  part;  but  the 
leaves  and  branches  with  the  southern  aspect  were  not  so  numerous 
nor  so  vigorous  as  the  others. 

The  dragon-tree  of  Orotava  in  the  Island  of  Teneriffe  is  one  of 
the  oldest  vegetable  monuments  of  the  present  world.  Humboldt 
gives  it  a  diameter  of  17  feet,  and  its  height,  as  stated  by  M.  Ledru, 
is  upwards  of  65  feet.  When  Teneriffe  was  discovered  in  1402, 
this  tree  appears  to  have  had  the  same  dimensions  which  it  presents 
at  the  present  time. 

The  mahogany  {cedrela  mahogani)  is  a  very  long-lived  tree.  In 
J..\maica  it  sometimes  acquires  a  diameter  of  upwards  of  6  feet,  and 
Sir  W.  J.  Hooker  has  calculated  that  two  centuries  at  least  are  re- 
quired to  supply  timber  of  the  large  scantling  which  we  constantly 
see  in  the  yards  of  our  timber  merchants  and  cabinet-makers. 

The  Hi/mencea  cnurbaril,  one  of  the  largest  trees  of  the  Antilles, 
yields,  like  mahogany,  a  timber  that  is  hard  and  in  great  request 
among  cabinet-makers  and  inlayers.  It  sometimes  grows  to  19  feet 
in  diameter. 

The  Baobab  {Adansonia  digitata)  lives  for  centuries,  and  acquires 
extraordinary  dimensions.  Adanson  saw  one  in  the  Cape  de  Verdes, 
in  the  trunk  of  which  an  inscription  was  found,  which  was  covered 
by  three  hundred  layers  of  wood  ;  it  had  been  cut  by  two  English 
travellers  three  centuries  before.  From  positive  observations  col- 
lected by  Adanson,  a  table  has  been  constructed  to  show  the  pro- 
gress and  probable  age  of  the  baobab : 


96  SIZE    AND    LONGEVITY    OP    TREES. 


Age  of  the  Baobab. 

Diameter  of  the  Trunk. 

Height. 

1  year, 

0.10  feet 

5.25  feet 

20 

1.04 

16.40 

30 

2.41 

23.30 

100 

a.84 

30.84 

1000 

14.76 

61.68 

2400 

19.03 

68.24 

5150 

31.99 

76.76 

De  Candolle  has  remarked  that  this  longevity  of  the  baobab  ia 
made  the  more  surprising  by  the  softness  and  liability  of  its  wood  to 
decay.  But  again,  it  must  be  considered  that  the  great  diameter  of 
the  trunk,  in  relation  to  the  height,  gives  the  tree  a  stability  which 
is  possessed  by  no  other — by  enabling  it  to  resist  violent  gales  of 
wind. 

It  strikes  me  that  there  may  very  well  be  some  mistake  in  Adan- 
son's  estimates  of  the  age  of  the  baobab.  When  we  see  such  irregu- 
larity in  the  growth  of  trees  of  the  same  species  planted  in  the  same 
soil,  little  reliance  can  be  placed  on  any  deductions  drawn  from  the 
size  of  the  trunk  when  the  concentric  rings  cannot  be  counted.  In 
proof  of  this  I  here  give  the  measurements  of  two  baobabs  planted  in 
1821  in  the  Botanical  Garden  of  French  Guiana.  In  1842  these 
trees  were  found : — 

feet.  feet. 

No.  1.  Length  of  stem  from  ground  Diameter  of  the  base 5.41 

to  first  branches 7.70  Do.  at  origin  of  branches 4.23 

«„  o  Tv>  QQR  Diameter  of  base 2.63 

"°-'*'^^ • ^'^  Do.  at  origin  of  branches 1.48 

In  the  tree  No.  2  the  branches  were  puny  and  nowise  in  relation 
with  the  size  of  the  trunk. 

The  bald  cypress  {taxodium  distichum)  is  a  tree  that  is  very 
abundant  in  Mexico,  and  in  the  southern  parts  of  the  United  States. 
At  Chapultepec  there  is  one  of  these  trees  called  the  cypress  of  Mon- 
tezuma, which  tradition  says  flourished  in  the  reign  of  that  prince. 
In  1831  the  tree  was  still  vigorous,  and  its  trunk  was  41  feet  in  cir- 
cumference. There  is  another  cypress  near  Oaxaca,  under  the 
shade  of  which  Fernando  Cortez  is  still  reported  to  have  rested  ;  the 
trunk  of  this  tree  is  upwards  of  39  feet  in  circumference,  and  it  is 
105  feet  in  heiglit.  Michaux  measured  several  taxodiums  in  the 
Floridas  which  approached  these  two  in  their  dimensions. 

We  have  only  uncertain  data  in  regard  to  the  age  which  palms 
may  attain  to ;  their  sizes,  however,  are  well  known.  In  Egypt, 
according  to  M.  Delille,  the  date-trees  are  generally  about  65  feet  in 
height.  In  the  Andes  of  Quindiu  several  ceroxylons  were  measured, 
the  trunks  of  which  were  from  195  to  230  feet  in  height !  Martius 
assigns  the  following  as  the  extreme  dimensions  of  the  palms  of  the 
Brazil-s  :  from  75  to  127  or  128  feet  in  height,  by  a  diameter  of  from 
6  to  about  12^  inches. 

Among  several  palms  {arica  oleacera)  planted  in  the  Botanical 
Garden  of  Cayenne  in  1821,  the  tallest  twenty  years  afterwards  was 


SIZE  AND  LONGEVITY  OF  TREES.  97 

i8  feet  from  the  ground  to  the  bottom  of  the  crown,  and  3  feet  6^ 
inches  in  circumference  at  the  base ;  at  6;^  feet  from  the  surface  of 
the  ground  the  circumference  was  only  2  feet  1  inch,  and  a  small 
fraction.  As  the  palms  and  baobabs  will  be  carefully  protected  in  the 
Botanical  Garden  of  Cayenne,  an  opportunity  wiL  je  afforded  future 
observers  of  following  these  plants  in  their  growth,  with  a  perfect 
assurance  of  being  correct  as  to  their  age. 

Particular  trees  of  different  kinds  have  occasionally  acquired  re- 
markable dimensions  and  lived  to  great  ages  in  Europe.  An  elm  is 
mentioned  which  grew  on  the  promenade  of  Morges,  the  age  of  which, 
reckoned  from  the  number  of  concentric  layers,  must  have  been 
three  hundred  and  thirty-five  years ;  its  trunk  was  above  18  feet  in 
diameter.  The  lime  is  another  tree  which  in  temperate  countries 
sometimes  grows  to  a  great  size.  The  one  planted  at  Freiburg  to 
commemorate  the  victory  of  Morat  in  1476,  in  1831  was  14i  feet  in 
diameter.  Near  the  same  place  there  is  another  tree  of  the  same 
kind  which  must  be  older  than  the  last,  inasmuch  as  it  was  already 
celebrated  for  its  size  a  century  ago  ;  in  1831  this  tree  was  upwards 
of  36  feet  in  circumference,  and  about  72  feet  in  height.  The 
lime-tree  of  Neustadt  is  scarcely  less  curious  for  its  size  and  the 
immense  spread  of  its  branches  than  for  the  historical  circumstances 
connected  with  it.  Looking  back  to  old  documents,  this  tree  must 
already  have  been  of  great  size  in  1229  ;  in  a  poem  written  in  1408 
we  are  told  that  this  tree  was  then  supported  by  sixty-seven  props ; 
in  1654  it  had  eighty-two  stone  pillars  to  support  its  branches,  and 
in  1831  the  number  had  increased  to  one  hundred  and  six.  The  cir- 
cumference of  the  trunk  at  6^  feet  from  the  ground  measured  very 
nearly  39  feet.  An  old  measurement  made  one  hundred  and  fifty 
years  before  corresponds  very  nearly  with  this,  a  fact  which  shows 
that  in  the  course  of  a  century  and  a  half  the  trunk  of  the  lime-tree 
of  Neustadt  had  not  grown  perceptibly.  It  is  said  to  be  from  seven 
to  eight  hundred  years  old.  The  old  lime-tree  of  Chaille  in  1801 
was  upwards  of  49  feet  in  circumference. 

The  beech  grows  rapidly  while  young  ;  but  in  more  advanced  age 
with  extreme  slowness.  In  1818  Deluc  saw  several  beeches  near 
Geneva,  the  trunk  of  which  was  from  14  to  16  feet  in  diameter. 

De  Candolle  measured  a  larch  two  hundred  and  fifty-five  years 
old,  the  trunk  of  which  was  upwards  of  5f  feet  (5.84  ft.)  in  diame- 
ter ;  and  a  larch  of  no  move  than  fifty-four  years  growth  has  been 
measured  which  was  more  than  3|  feet  in  diameter. 

The  celebrated  chestnut-tree  of  Mount  Etna  has  been  stated  to  be 
upwards  of  206^  feet  in  girth,  (about  68  feet  in  diameter,)  an-i  must 
therefore  be  the  largest  tree  described  up  to  the  present  time  ;  but 
the  tree  has  been  supposed  to  be  formed  by  several  trunks  springing 
from  a  common  root  which  have  grown  together.  Other  remarka- 
ble chestnut-trees  are  mentioned. 

The  plane  is  one  of  the  largest  growing  trees  of  temperate  coun- 
tries. A  traveller,  who  visited  the  valley  of  Bujukdere,  near  Con- 
stantinople, met  with  a  plane  upwards  of  95  feet  in  height,  and  the 
trunk  of  which,  hollow  internally  down  to  the  levpl  of  the  ground, 

9 


98  SIZE  AND  LONGEVITY  OF  TREES. 

«ras  more  than  154  feet  in  circumference.  A  plaae-tree,  which 
grew  in  Norfolk,  and  was  of  the  age  of  thirty-one  years,  was  T{ 
feet  in  circumference,  according  to  Hunter.  Cypress-trees  often 
attain  to  a  very  great  age.  In  the  garden  of  the  palace  of  Grenada 
there  is  one  which  has  stood  for  more  than  three  centuries.  iVt  La 
Somma,  near  Milan,  a  cypress  is  shown  which  in  1794  was  17  feet 
in  circumference,* 

Tradition  has  it  that  an  orange-tree  of  the  convent  of  St.  Sabina 
at  Rome,  was  planted  by  St.  Dominic  in  the  year  1200  ;  this  tree 
still  exists.  The  orange-tree  of  Versailles,  known  under  the  name  of 
the  Francis  /.,  is  rather  more  than  three  hundred  years  old.  In  1804, 
orange-trees  were  shown  in  the  green-houses  of  Bonn  three  centu- 
ries old,  and  of  which  the  trunks  were  more  than  30  inches  in  cir- 
cumference.! In  South  America  I  had  myself  occasion  to  observe 
citron-trees  of  great  age  and  of  very  considerable  dimensions  ;  the 
trunks  of  several  of  these  trees  were  nearly  27|  inches  in  diameter. 

A  sycamore-tree  of  the  village  of  Trons,  in  the  Grisons,  more 
than  five  hundred  years  old,  is  at  this  time  between  8  and  9  feet  in 
diameter. 

Many  oaks  have  been  described  which  had  survived  from  eight 
hundred  to  one  thousand  years.  Hunter  saw  one  of  these  trees  still 
extremely  vigorous  which  was  IH  feet  in  diameter.  Evelyn,  who, 
in  his  delightful  work  entitled  Sylva,  has  given  a  list  of  the  largest 
oaks  known  in  his  day  in  England,  speaks  of  one  growing  in  Wel- 
beck  Lane  which  must  have  been  eight  hundred  and  sixty  years  old 
at  least,  and  the  diameter  of  whose  trunk  at  the  base  was  upwards 
of  12|  feet. 

The  olive  is  one  of  the  trees  that  reaches  a  great  age  ;  Picconi 
describes  one  of  about  seven  centuries,  and  a  circumference  of  about 
25  feet. 

The  cedar  of  Lebanon  grows  vigorously  and  long,  especially  in 
soils  that  are  sufficiently  loose  and  permeable.  According  to  M. 
Paul  Vibray,  of  Sologne,  the  growth  of  this  tree  is  more  rapid  than 
that  of  the  coniferi  in  general.  The  cedars  which  grew  on  Mount 
Lebanon,  and  were  measured  by  Nauwolff  in  1574,  and  again  by 
Labillardiere  in  1787,  are  generally  allowed  to  be  about  the  age  of 
one  thousand  years.  De  Candolle,  however,  thinks  that  this  age  is 
exaggerated,  and  in  contradiction  with  observations  made  on  troes, 
the  age  of  which  is  positively  known.  The  following  are  a  few  of 
the  measurements  which  have  been  reported  by  different  observers 

An.  feet  circiimrer.   Obwrrtrs. 

CedRr  of  Chelsea 83  12 

"  olPHris 40  7  Thou.n. 

"  nl'ditio 83  9.4  Loiseletf 

"  Environs  of  London 200  16  Hunter 

"  Ditto 113  14  Ditto. 

*♦  of  Mount  l^sbanun 600  36.4  MaundreL 

"  ofSologne 30  5  ofVit«y 

Tbe  yew,  as  is  well  known,  produces  a  very  hard,  close,  and  e» 

•  De  C&ndoUe,  Physiolosie,  p.  9M.  t  Ibid.  p.  SOB. 


AGE    FOR    FELLING.  90 

during  wood,  qualities  which  contribute  greatly  to  the  longevity  of 
trees.  Some  of  the  oldest  trees  known  have  been  yews.  Here  are 
a  few  that  have  been  particularly  described  : 

Where  they  ^ow.  Probable  tige.  Circumference.  Observeri. 

County  of  York 1220  28.25  Pennant 

Ditto 1220  13.85  Ditto. 

County  of  Surrey 1287  30.12  Evelyn. 

Fotheringal  (Scotland) 2580  62-34  Pennant, 

CountyofKent 2800  62.60  Evelyn. 

According  to  Duhamel  it  is  extremely  difficult  to  fix  upon  any  age 
as  the  best  in  a  general  way  for  felling  trees,  with  a  view  to  ob- 
taining the  largest  quantity  of  sound  available  timber.  When  the 
tree  is  too  young,  the  timber  has  not  all  the  excellence  which  it 
would  have  gained  with  greater  age ;  when  too  old,  the  pores  are 
obstructed,  and  it  has  begun  to  decay  in  the  parts  of  oldest  forma- 
tion, so  that  it  is  not  uncommon  to  find  wood  in  the  centre  of  the 
trunk  which  is  lighter  than  that  of  the  circumference.  In  trees 
which  have  already  fallen  into  a  certain  state  of  decay,  the  worst 
timber  in  them  is  decidedly  that  which  is  taken  from  the  centre  at 
the  base  of  the  trunk  ;  and,  indeed,  the  wood  of  the  centre  generally 
is  then  of  inferior  quality  to  that  of  more  recent  formation.  Very 
aged  timber  always  perishes  first  in  those  parts  which  have  formed 
the  most  internal  layers  of  the  tree.  It  is,  therefore,  an  obvious  and 
grave  error  to  suffer  any  tree  to  stand  that  has  given  the  slightest 
indications  of  decay,  inasmuch  as  that  which  is  ordinarily  the  most 
valuable  limber  is  likely  to  be  altogether  lost.  Neither  the  age  nor 
the  dimensions  are  always  the  indications  of  the  proper  period  for 
felling  trees ;  exposure,  soil,  situation,  have  immense  influence  upon 
their  growth,  vigor,  and  general  qualities.  Trees  ought  to  be  cut 
just  when  they  are  on  the  turn  ;  the  proper  moment  is  that  which 
precedes  immediately  the  alteration  of  the  heart;  and  although  the 
destructive  eflfects  of  age  are  principally  felt  in  the  interior,  this  in- 
testine disorder  is  nevertheless  proclaimed  externally ;  the  whole 
tree  suffers  when  it  has  taken  place.* 

Duhamel  has  given  the  following  characters,  as  indicating  in- 
cipient decay,  or  decline  of  vigor  in  trees  :t 

1.  A  tree,  the  top  of  which  forms  one  uniform  rounded  mass,  is 
not  strong ;  a  vigorous  tree  always  throws  out  certain  branches 
which  surpass  the  others  in  luxuriance  of  growth, 

2.  When  a  tree  comes  into  leaf  prematurely  in  the  spring,  and 
particularly  when  the  leaves  turn,  and  fall  prematurely  in  the  autumn, 
it  is  a  certain  sign  of  weakness. 

3.  When  several  of  the  top  or  leading  branches  of  a  tree  die, 
even  at  their  mere  extremities,  the  wood  in  the  centre  is  beginning 
to  undergo  alteration. 

4.  When  the  bark  quits  the  trunk,  or  becomes  cracked  here  and 
there,  we  may  be  satisfied  that  the  tree  is  far  gone  internally. 

5.  Mosses,  lichens,  and  funguses  growing  upon  the  bark,  and  red 

*  Duhamel,  Exploit,  des  bois,  t.  i.  p.  126.  t  Idem,  1. 1,  p.  133^ 


idO  SEASON    FOR    FELLING. 

or  black  spots  appearing  upon  it,  always  lead  to  a  suspicion  of  change 
in  thf;  wood. 

6.  When  the  sap  is  observed  to  flow  from  crevices  in  the  bark, 
the  death  of  the  tree  is  at  hand. 

In  I'rance,  the  cutting  dowr  of  the  smaller  wood,  such  as  is  used 
for  firing,  takes  place  at  from  twenty  to  thirty  years ;  in  the  forests, 
the  trees  are  commonly  felled  at  from  one  hundred  to  one  hundred 
and  thirty  years  old,  and  a  few  trees  are  generally  left  as  reserves, 
and  for  special  purposes,  till  they  have  attained  the  age  of  from  two 
hundred  to  two  hundred  and  fifty  years. 

The  prevalent  opinion  among  foresters,  with  regard  to  the  proper 
season  for  felling,  is,  thLt  it  should  be  done  when  the  sap  is  in  the 
state  of  greatest  repose,  or  when  it  is  present  in  least  quantity  in  the 
trees.  The  season  fixed  by  the  old  law  of  France  (1669)  was  from 
October  to  March  inclusive.  But  the  experiments  of  Duhamel  tend 
to  show  that  this  is  not  actually  the  season  when  trees  contain  the 
smallest  proportion  of  sap,  and  that  fellings  made  at  other  times  of 
the  year  have  had  very  satisfactory  results.  All  things  well  weighed, 
says  the  illustrious  cultivator,  our  only  safe  guide  in  such  matters  is 
observation ;  and  from  numerous  experiments  he  concluded  that 
there  was  actually  as  much  sap  in  trees  in  winter  as  in  summer,  and 
that  the  spring  and  summer  were  the  seasons  most  favorable  for  the 
speedy  drying  of  the  timber.  Trees  felled  in  summer  were  even 
found  by  Duhamel  to  yield  timber  which  stood  better  and  lasted 
longer  than  those  that  were  cut  down  in  winter ;  while  he  found  the 
wood  of  equal  strength  in  either  case.  He  concluded,  therefore, 
that  the  season  of  the  year  at  which  timber  was  felled,  had  no  in- 
fluence upon  its  quality  or  durability.* 

There  is,  in  fact,  no  general  rule  observed  in  different  countries 
as  to  the  period  at  which  timber  is  felled.  The  French  still  go  on 
cutting  from  October  to  March ;  the  English  fell  in  the  winter. 
Convenience  of  different  descriptions  appears  often  to  decide  the 
question  as  to  season.  In  order  to  procure  bark  for  the  tanneries, 
an  act  was  passed  by  the  English  Parliament  in  1603,  prohibiting 
all  felling  of  oak  timber  during  the  dead  season,  the  penalty  for  in- 
fringement of  the  act  being  confiscation  of  the  timber  felled,  or  fine 
to  the  amount  of  twice  its  value.  An  exception,  however,  was  still 
made  in  regard  to  timber  destined  for  the  public  service  in  ship- 
building, &c.  The  price  of  bark  afterwards  rose  to  such  a  height, 
that  it  was  found  most  profitable  to  cut  in  the  spring ;  and  the  prac- 
tice then  became  so  general,  that  it  by  and  by  became  necessary  to 
offer  premiums  to  induce  proprietors  of  oak  forests  to  fell  timber  in 
the  winter  season,  for  the  sake  of  the  British  navy.  The  inhabitants 
of  the  county  of  Stafford  appear  at  a  somewhat  early  period  to  have 
sought  to  combine  the  advantages  of  the  bark  trade,  with  a  fulfil- 
ment of  the  conditions  that  entitled  them  to  the  premium  on  winter- 
felled  timber  :  they  stripped  the  trees  of  their  bark  in  the  spring, 
and  felled  them  the  following  winter.     And  Buffbn  and  Duhame. 

♦  Dnhamel,  op.  cit.,  t,  i.  p.  400 


INFLUENCE  OF  SOIL  ON  TIMBER.  101 

ihowed  subsequently,  that  by  barking  trees  two  or  even  three  years 
before  cutting  them  down,  the  white  external  wood  could  be  render- 
ed nearly  as  hard  and  durable  as  the  heart- wood  of  the  tree.  The 
iccommendation  of  this  procedure  by  these  two  distinguished  men 
has  not  been  followed  in  France ;  but  ever  since  1770  the  Dutch 
have  adopted  it,  and  it  is  now  practised  in  many  parts  of  England, 
particularly  in  the  royal  forests. 

It  is  quite  certain  that  the  nature  of  the  soil  exerts  a  considerable 
influence  on  the  rapidity  of  growth  and  quality  of  the  timber.  The 
oak,  the  elm,  &c.,  which  have  been  grown  in  a  damp  soil,  will  not 
be  so  hard  and  compact  as  the  same  trees  reared  on  a  dry  plot. 
Duhamel  found,  that  although  the  trees  which  came  in  swampy  bot- 
toms were  very  sappy  and  wet,  they  were  still  lighter  than  others 
of  the  same  kind  which  had  grown  on  a  dry  bank.  Their  white 
wood  is  thick  in  comparison  with  their  hard  wood  ;  they  are  brittle, 
and  do  not  readily  take  or  keep  the  shapes  into  which  they  are  bent 
for  ship-bu'lding  or  for  staves  ;  and  then  their  pores  being  large  and 
open,  and  the  whole  wood  being  without  that  kind  of  varnish  which 
impregnates  good  timber,  they  are  readily  permeable  and  unfit  for 
the  manufacture  of  vats,  &c. — to  say  nothing  of  their  being  much 
more  perishable.  Such  soft  and  porous  timber  is  altogether  im- 
proper for  out-of-door  constructions  and  for  ship-building ;  but  it 
answers  extremely  well  for  indoor  and  cabinet  work  ;  for  the  latter 
it  has  even  certain  advantages,  it  is  easily  wrought ;  and  once  fairly 
seasoned,  it  is  neither  so  apt  to  warp  nor  to  crack  as  harder  wood. 
It  was  very  probably  to  guard  against  any  excess  of  sap  in  trees,  so 
prejudicial  in  a  general  way  to  the  timber  they  yield,  that  the  Ro- 
mans, according  to  Vitruvius,  surrounded  those  that  were  destined  to 
be  cut  down  with  a  trench  six  months  beforehand.* 

Trees  which  have  grown  in  a  good  soil  sufficiently  drained  have 
a  fine  bark,  and  their  white  wood  is  moderate  or  small  in  quantity. 
Their  woody  layers,  indeed,  are  apt  to  be  thinner  generally,  than 
those  of  trees  that  have  grown  in  a  wet  soil  ;  but  they  are  much 
harder  and  tougher,  their  grain  is  more  even  and  close,  and  their 
pores  are  filled  with  an  incrusting  matter.  They  are  consequently 
very  heavy,  even  when  thoroughly  dry,  and  with  time  and  due 
seasoning  they  become  extremely  hard,  and  in  the  same  degree 
acquire  durability.  Duhamel  was  led  by  his  experiments  to  conclude 
that  the  difference  in  point  of  density  of  timber  grown  in  a  marshy 
soil,  and  in  one  that  was  well  drained  and  dry,  was  occasionally  in 
the  ratio  of  five  to  seven. 

The  denser,  dry-grown  timber  supports  a  relatively  much  greater 
weight  without  breaking  than  the  marsh-grown  timber  ;  and  when 
it  does  yield,  it  gives  way  by  a  large  and  splintering  surface,  while 
the  softer,  less  dense  wood  snaps  off  short.  In  brief,  there  is  na 
question  as  to  which  kind  of  timber  is  the  most  valuable  ;  and  meas- 
ures ought  to  be  taken  by  landed  proprietors  and  timber-growers  at 
all  times,  not  merely  to  grow  trees,  but  to  grow  them  under  such  cir- 

*  Duhamel,  Expl.  de-^  bois  t.  i.  p  46. 
9* 


102  SEASONINO. 

cumstances  as  shall  ensure  their  yielding  good  available  timber  when 
they  have  come  to  maturity. 

If  wet  soils  then  be  uniavorable  to  the  growth  of  timber  of  the 
highest  value,  in  ship-building  especially,  what  has  been  said  must 
be  taken  as  of  application  to  those  trees  only  which  will  grow  in  a 
great  variety  of  soils.  Damp  and  even  marshy  lands  are  well  known 
to  be  favorable  and  even  indispensable  to  certain  trees,  which,  by 
their  nature,  delight  in  the  neighborhood  of  water ;  but  these  are 
generally  kinds  which  are  rather  sought  after  for  their  height  and 
lightness,  than  for  their  strength  and  durability.* 

Excessively  dry  soils,  on  the  other  hand,  have  also  their  disad- 
vantages for  forest  cultivation.  In  such  ground,  trees  seldom  ac- 
quire a  sufficient  growth  to  admit  of  their  being  applied  to  any  im- 
portant purpose.  It  is  certain,  however,  that  absolute  uniformity  is 
never  encountered  in  any  piece  of  timber.  The  woody  layers  that 
have  been  formed  in  a  wet  or  a  dry  year,  in  a  warm  or  a  cold  year, 
feel  and  manifest  the  effects  of  the  varying  meteorological  influences. 
They  are  of  different  thicknesses  and  densities,  and,  when  carefully 
examined,  are  found  to  present  the  characters  of  the  timber  grown  in 
soils  of  the  most  opposite  description  in  point  of  wetness  and  dry- 
ness.f 

The  treatment  of  trees  after  they  are  felled,  the  drying  and  sea- 
soning of  the  timber,  are  points  of  the  highest  importance.  Standing 
trees  contain  a  large  quantity  of  water  in  their  composition.  After 
being  cut  down  the  moisture  is  dissipated,  rapidly  at  first,  much 
more  slowly  afterwards.  This  drying  process  is,  of  course,  favored 
or  retarded  by  the  varying  states  of  heat  and  moistness  of  the  atmo- 
sphere. At  length  there  comes  a  time  when  the  wood  no  longer 
suffers  any  sensible  change  by  longer  exposure  to  the  air ;  or  if  it 
does,  the  change  is  now  on  the  one  side,  now  on  the  other,  and 
merely  in  harmony  with  the  hygrometric  state  of  the  atmosphere. 
Timber  has  then  lost  the  whole  of  the  moisture  which  it  can  get  rid 
of  by  this  mode  of  drying  ;  it  is  now  fit  for  use ;  it  is  seasoned,  to 
use  the  technical  expression. 

Timber  is  sometimes  seasoned  by  previous  total  immersion  in 
water.  It  has  been  held  that  this  process  favored  the  thorough  dry- 
ing, by  dissolving  out  certain  deliquescent  salts  which  are  found  in 
the  sap,  and  prevented  after-shrinking.  However  this  may  be,  ii  is 
quite  certain  that  in  warm  countries  especially,  it  is  advantageous  to 
sink  fresh-cut  timber  in  water,  with  a  view  to  prevent  it  from  split- 
ting, apparently  in  consequence  of  drying  too  quickly.  The  old 
Venetians  sank  for  a  season  in  the  sea,  the  oak  timber  which  was 
destined  for  the  construction  of  their  galleys.  Elm  and  beech,  in 
particular,  are  said  to  improve  greatly  by  the  process  of  submersion 
in  salt  water,  and  to  dry  afterwards  perfectly  by  simple  exposure  to 
the  air  ;|: 

*  We  believe,  however,  that  the  live-oak,  of  which  the  American  navy  Is  con- 
structed, and  which  supplies  one  of  the  most  imperishable  kinds  of  timber  kuown 
frow.s  exclusively  in  swamps.— Eno.  Ed 

t  Duhamel,  t.  i.,  p.  57. 

i  Knowlos,  Maritime  and  ColooialAnnaU,  1885. 


DECAY.  103 

Mr.  John  Knowles,  who  made  a  particular  study  of  the  means 
most  generally  employed  in  seasoning  timber,  has  given  an  account 
of  a  series  of  experiments  undertaken  in  the  arsenals  of  Deptford 
and  Woolwich,  to  determine  the  rate  of  drying  and  ultimate  degree 
of  dryness  attained  by  timber  variousty  treated — unprepared  and 
prepared  by  previous  submersion  in  water.  The  pieces  of  timber 
were  placed  vertically,  now  in  the  position  they  had  occupied  in 
growing,  now  in  that  opposed  to  this  ;  and  it  was  found  that,  circum- 
stances the  same,  they  dried  more  quickly  in  the  former  than  .n  the 
latter.  The  general  results  of  these  experiments  were  as  follows : 
1st.  That  the  pieces  of  timber  were  best  seasoned  by  being  kept 
about  thirty  months  in  the  air,  but  in  the  shade  and  protected  from 
wet.  2d.  That  they  lost  more  of  their  original  weight  after  six 
months'  alternate  immersions  and  dryings,  than  by  being  kept  under 
water  for  six  months  and  then  dried.  Ship-builders  are  generally 
agreed  that  it  is  not  expedient  to  make  use  of  timber  until  three 
years  after  it  is  cut.* 

Duhamel  advises  strongly,  that  in  ship-building  all  timber  from 
trees  already  on  the  decline  should  be  rigorously  rejected  ;  and  this 
the  rather,  that  the  most  careful  examination  often  fails  at  first  to 
perceive  any  alteration  in  the  heart-wood  of  such  trees,  although  it 
never  fails  to  show  itself  by  and  by  at  a  sufficient  interval  after  the 
felling.  This  is  undoubtedly  a  precept  which  it  would  be  well  to 
bear  constantly  in  mind  ;  but  timber  does  not  always  carry  within 
itself  the  germs  of  its  speedy  decay  ;  and  that  which  has  been  sea- 
soned with  the  most  scrupulous  care,  and  was  originally  of  the  best 
quality,  does  not  escape  the  rot  when  it  is  placed  under  unfavorable 
circumstances,  any  more  than  that  which  was  of  inferior  worth  and 
less  carefully  treated. 

Wood  appears  to  perish  or  decay  through  three  principal  a  d  ap- 
preciable causes,  which  all  require  similar  conditions  to  con  i  into 
play,  viz.,  stagnant  air,  sufficient  warmth,  and  moisture.  Like  the 
generality  of  organic  substances,  wood,  when  moistened  in  contact 
with  the  oxygen  of  the  air,  and  under  the  influence  of  a  sufficiently 
high  temperature,  undergoes  decomposition  of  a  kind  which  has  been 
compared  to  a  slow  combustion,  upon  which  we  shall  find  occasion 
to  say  more  by  and  by.  It  is  with  a  view  to  escape  this  kind  of  de- 
cay as  much  as  possible  that  timber  is  never,  or  ought  never,  to  be 
employed  in  the  construction  of  ships  and  buildings  until  it  has  been 
thoroughly  seasoned. 

Besides  this  first  cause  of  decay,  which  may  be  prevented  in  a 
great  measure  by  using  certain  precautions,  wood  has  still  two  re- 
doubtable enemies,  insects  and  certain  plants  of  the  family  of  the 
cryptogamiae.  In  one  case,  the  wood  perishes  because  it  is  fed  upon 
by  certain  animals  which  live  and  grow  at  its  expense ;  in  the  other 
it  decays  because  it  serves  as  the  soil  to  one  crop  of  fungus  after 
another  which  luxuriate  on  its  surface,  while  their  roots  penetrate 
deeply  into  its  interior.    There  is  nothing  in  either  accident  which 

•  Dapln,  Ann.  de  CaUmie,  t  xvii.  p^  S77. 


104  DRY-ROT. 

excites  astonishment,  now  that  we  know  the  intimate  coi.stitution 
of  wood.  We  know,  in  fact,  that  amon^  the  number  of  sohible 
principles  which  impregnate  the  woody  tissue,  there  is  an  azotized 
matter  analogous  in  its  composition  to  those  that  exist  so  abundantly 
in  all  the  ordinary  esculent  vegetables.  There  is,  therefore,  in  wood 
ample  nourishment  for  the  insects  which  we  find  living  on  it ;  and 
if  I  state  now  (reserving  to  myself  the  opportunity  of  demonstrating 
the  fact)  that  all  organic  azotized  matter  becomes  an  active  manure 
by  decaying,  we  shall  understand  how  it  happens  that  plants,  which 
have  the  power  of  living  in  dark,  warm,  and  damp  places,  wax  and 
multiply  in  the  joistings  of  houses,  and  in  the  ribs  and  planks  ol 
hips,  causing  a  dry  rot,  which  separates  the  integral  layers  of  the 
wood,  and  reduces  the  strongest  beams  to  dust. 

The  rapidity  with  which  wood  is,  in  some  circumstances,  devour- 
ed by  insects  is  almost  incredible.  Some  years  ago  the  thermites, 
or  white  ants,  spread  in  such  strength  through  the  docks  and  ar- 
senals of  Roehelle  and  Rochefort,  that  in  a  very  short  space  of  time 
serious  damage  was  done.  A  learned  entomologist,  M.  Audouin, 
commissioned  by  the  ministry  to  take  information  on  the  subject, 
reported  that  the  ravages  committed  by  these  insects  had  been  very 
considerable.  But  it  is  principally  in  warmer  climates,  where  the  tem- 
perature is  steady  throughout  the  year,  and  where  there  is  no  winter, 
that  the  thermites  occasion  the  most  alarming  injury.  At  Popayau, 
for  example,  it  is  difficult  to  meet  in  a  building,  even  of  recent  con« 
struction,  with  a  piece  of  wood  which  is  not  gnawed  and  ant-eaten. 
The  hardest  and  most  compact  woods  do  not  always  resist  the  at- 
tacks of  these  insects,  which,  further,  do  not  spare  every  kind  of 
odorous  wood,  cedar  for  instance.  In  such  countries  it  is  altogether 
imp.  ssible  to  preserve  books  and  papers.  I  remember,  in  connec- 
tion vith  this  matter,  that  having  received  instructions  to  examine 
the  archives  of  Anserma,  one  of  the  oldest  towns  in  Popayan,  in 
1830,  I  found  nothing  but  books  illegible  and  in  pieces ;  neverthe- 
less, the  date  of  the  documents,  which  it  was  my  business  to  con^ult, 
could  not  have  been  older  than  the  year  1600. 

The  dry  rot,  which  results  from  the  development  and  growth  of 
cryptogamic  plants  upon  wood,  is  the  curse  of  navies.  Mr.  Knowles 
is  of  opinion  that  this  disease  of  timber  has  been  known  from  the 
most  remote  antiquity ;  he  believes  that  he  can  even  recognise  dry- 
rot  in  the  sore  called  house-leprosy,  mentioned  in  the  14th  chapter 
of  Leviticus.  A  ship  attacked  by  dry-rot,  becomes  in  a  very  short 
space  of  time  unfit  for  sea.  The  Foudroyant  of  80  guns  is  often 
quoted  as  an  instance  of  its  destructive  powers  :  launched  in  1798, 
she  had  to  be  taken  into  dock  and  almost  rebuilt  so  soon  as  1802.* 

The  fungi  which  induce  dry-rot  have  been  studied  by  Sowerby. 
Mr.  Knowles  signalizes  two  species  in  particular  ;  one  of  which  he 
describes  under  the  name  of  Xylostroma  giganteum,  the  other  under 
that  of  Boletus  lacrymans.  The  Xylostroma  does  not  extend  beyond 
the  part  where  it  is  developed  ;  but  the  Boletus,  on  the  coalrary,  it 

*  Pupia,  Ann.  de  Chimle,  t.  xvii.  p.  290i 


PRESERVATION  OF  TIMBER.  105 

piDpagated  with  frightful  rapidity,  and  disorganizes  deeply  and  to  a 
great  distance  around  the  texture  of  the  wood  where  it  once  appears 
These  fungi  are  generally  found  on  board  ship,  between  the  planking 
and  the  ribs,  in  damp  situations,  and  where  the  air  is  scarcely,  if 
ever,  changed.* 

The  temperature  most  favorable  to  the  development  of  dry-rot  has 
been  found  to  lie  between  T  and  32"  cent,  or  45°  and  90°  F.  These 
are  the  extreme  limits  :  below  the  minimum  vegetation  languishes  ; 
above  the  maximum,  the  fungi  droop.  With  this  piece  of  informa- 
tion it  was  hoped  that  vessels  might  be  freed  from  dry-rot  by  raising 
the  temperature  sufficiently.  The  trials  were  made  in  winter  in  the 
"  Queen  Charlotte,"  the  air  in  the  lower  part  of  the  ship  being  raised 
as  high  as  55°  cent,  or  130°  F.  But  the  general  result  did  not  an- 
swer expectations  ;  for  although  the  fungi  were  destroyed  in  the  low- 
er part  of  the  vessel,  it  was  found  that  their  growth  was  rather  fa- 
vored in  places  at  a  certain  elevation  above  the  kelson.  The  warm 
air,  in  fact,  as  it  rose  through  the  timbers  became  robbed  in  its  course, 
and  deposited  the  greater  portion  of  the  moisture  which  it  had  taken 
up  at  a  lower  level.  Above  the  orlop  deck,  consequently,  there  was 
just  about  the  temperature  and  the  quantity  of  moisture  most  favora- 
ble to  the  development  of  the  fungi.  The  evil  was  therefore  only 
transplanted,  not  destroyed.  It  was  now  proposed  to  heat  the 
"'tween  decks"  at  the  same  time  as  the  hold,  making  use  of  due 
ventilation  ;  but  this  method  of  p'-oceeding  has  not  been  put  intp  prac- 
tice. 

The  extreme  slowness  of  the  growth  of  trees  stands  in  strong  con- 
trast with  the  rapidity  of  their  decay  when  they  are  reduced  to  the 
shape  of  timber  and  employed  in  constructions  of  almost  every  kind. 
In  countries  well  advanced  in  civilization,  every  description  of  in- 
dustry tends  to  consume  timber,  at  the  same  time  that  an  increas- 
ing population  is  every  day  contracting  the  extent  of  forest  land, 
and  diminishing  the  number  of  trees  grown.  In  some  countries,  in- 
deed, it  is  certain  that  the  production  of  wood  for  all  purposes,  firing, 
&c.,  &c.,  is  no  longer  in  relation  with  its  consumption.  The  price 
of  the  article,  necessarily  high,  is  therefore  tending  continually  to 
rise ;  and  it  is  not  surprising  that  various  measures  have  been  sug- 
gested and  essayed  of  giving  this  perishable  material  greater  dura- 
bility. 

The  well-known  great  durability  of  certain  trees,  the  teak,  ebony, 
lignum-vitae,  &c.,  naturally  led  to  the  conclusion  that  the  fatty  or 
resinous  matters  which  they  contain  have  the  property  of  preserving 
the  wood  against  the  greater  number  of  the  ordinary  causes  of  de- 
cay ;  and  unctuous  and  resinous  matters  appear  in  fact  to  have  been 
•he  means  most  anciently  employed  to  preserve  wood  from  the  air, 
from  moisture,  and  from  the  attacks  of  insects.  But  it  is  scarcely 
necessary,  at  the  present  time,  to  say  that  these  varnishes  only  ac- 
complish the  object  proposed  in  their  application  in  a  very  imperfect 
wa^  ;  paint  and  varnishes  crack,  rub,  or  scale  off  with  the  slightest 

•  Dupin,  Ann.  de  Chimie  et  de  Physique^  t.  xvii.  p.  291,  tie  »*ne. 


106  PRESERV^ATION  OF  TLMBER. 

friction ;  nor  do  they  always  remove  the  causes  of  internal  decay 
on  the  contrary,  by  preventing-  more  complete  dryness,  they  some- 
times even  provoke  or  favor  them,  when  applied  to  tender,  that  is, 
imperfectly  seasoned  wood.  Merely  laid  on  the  surface,  indeed,  it 
his  always  been  seen  that  varnishes  of  any  kind  were  but  indifferen* 
protectors  ;  that  a  really  good  preserver  ought  to  penetrate  the  sub- 
stance of  ti..v3  wood,  and  unite  with  the  tissue  itself.  But  herein  lay 
the  whole  difficulty  ;  how  was  the  needful  penetration  to  be  effected  1 
for  the  number  of  chemical  substances,  from  which  good  effects 
might  reasonably  be  anticipated,  is  pretty  considerable, — unless  in- 
deed we  find  ourselves  prevented  from  using  them  by  the  considera- 
tion of  the  price ;  for  it  is  imperative  that  any  preservative  proposed 
be  extremely  cheap. 

For  a  long  time  the  only  process  for  effecting  the  penetration  of 
timber  by  substances  proposed  for  its  preservation  was  to  macerate 
them  for  a  longer  or  shorter  time  in  a  solution  of  the  substance. 
But  this  means  was  found  as  tardy  of  accomplishment  as  it  was  or- 
dinarily imperfectly  effected  ;  to  have  got  to  the  heart  of  logs  of 
large  scantling,  years  would  have  been  required.  Any  delay,  how- 
ever, in  such  circumstances,  is  of  itself  a  cause  of  enhanced  price 
of  the  article.  By  and  by  a  variety  of  processes,  the  element  in  one 
being  pressure,  in  another  exhaustion,  were  put  in  practice,  and  very 
satisfactory  results  obtained.  M.  Breant  showed,  that  by  means  of 
strong  pressure  he  could  fill  the  largest  logs  from  one  end  to  the 
other  with  any  unctuous  or  resinous  substance  proposed,  in  the  course 
of  a  few  minutes.  M.  Moll,  a  learned  German,  proposed  creosote 
introduced  in  the  state  of  vapor  by  forcing,  as  an  effectual  means  of 
preserving  timber,  which  it  probably  would  be  found ;  but  the  high 
price  of  the  antiseptic,  were  there  no  other  objections,  would  neces- 
sarily be  an  obstacle  to  its  general  employment.  The  same  objection 
applies  to  the  bichloride  of  mercury,  (Kyan's  patent;)  and  arsenic  is 
inadvisable  from  its  deleterious  effects  upon  the  animal  economy. 
Some  workmen  are  said  to  have  lost  their  lives  in  consequence  of 
working  timber  which  had  been  impregnated  with  a  solution  of  whit(» 
oxide  of  arsenic. 

It  had  been  observed  that  vessels  engaged  in  the  lime-trade  lasted 
long ;  and  then  it  was  naturally  thought  that  by  impregnating  the 
wood  to  be  used  for  ship-building  with  lime  it  would  be  rendered 
more  durable.  But  the  result  did  not  answer  expectation  ;  the  tim- 
ber treated  with  lime  did  not  even  seem  to  last  the  usual  time.* 

Such  was  the  state  of  the  question  when  Dr.  Boucherie  made  a 
highly  important  communication  to  the  Royal  Academy  of  Sciences 
on  the  preservation  of  timber. f  Some  estimate  of  its  nature  may 
be  formed  from  the  list  of  subjects  discussed  in  this  remarkable 
paper. 

1.  To  protect  timber  against  dry-rot  and  the  ordinary  wet-rot 

2.  To  increase  its  hardness  and  strength. 

3.  To  ppjserve  its  flexibility  and  elasticity. 

•  Dupin,  Ann.  de  Chlmle,  t.  xvil.  p.28S 
t  Idem,  t.  Ixxiv.  p.  113. 


PRESERVATION   OF   TIMBER.  107 

4.  To  counteract  its  alternate  contraction  and  expansion  in  conse- 
quence of  the  varying  state  of  moisiness  and  temperature  of  the 
atmosphere. 

5.  To  diminish  its  inflammability  and  combustibility. 

6.  To  give  it  a  variety  of  permanent  colors  and  odors. 

In  the  whole  of  his  experiments  M.  Boucherie  set  out  from  this 
proposition,  the  truth  of  vv^hich  appears  indisputable  and  to  require 
no  comment,  viz  :  That  all  the  changes  which  wood  undergoes  pro- 
ceed or  depend  upon  the  soluble  matters  which  it  contains.  In  confor- 
mity with  this  idea,  the  first  step  towards  giving  durability  to  timber 
was,  either  to  render  these  matters  insoluble  and  inert,  or  to  remove 
them  entirely.  M.  Boucherie,  therefore,  in  his  first  trials  sought  to 
render  the  matters  insoluble  by  charging  the  wood  with  a  substance 
capable  of  combining  chemically  and  forming  a  precipitate  with  the 
soluble  matter  left  by  the  sap.  To  resolve  this  problem,  M.  Boucherie 
investigated  the  reactions  between  the  soluble  matter  of  wood,  which 
it  was  his  object  to  precipitate,  and  a  variety  of  low-priced  chemical 
agents.  He  found  that  the  pyrolignite  of  iron  combined  the  greatest 
number  of  desirable  properties  :  it  is  very  cheap,  the  oxide  of  iron 
forms  stable  compounds  with  the  greatest  number  of  the  organic 
substances  which  are  found  in  the  sap  of  vegetables,  and,  to  conclude, 
the  crude  pyrolignite  contains  a  notable  quantity  of  creosote. 

The  facts  upon  which  M.  Boucherie  relies  as  proving  the  preser- 
vative powers  of  the  pyrolignite  of  iron  flow  from  numerous  experi- 
ments performed  either  on  vegetable  substances  which  in  themselves 
readily  and  rapidly  undergo  changes  ;  or  upon  billets  of  wood  of 
diflferent  kinds.  A  quantity  of  flour,  the  pulp  of  carrots,  beet-roots, 
&c.,  impregnated  with  the  pyrolignite  resist  decomposition  in  a  very 
remarkable  manner  in  contrast  with  the  same  substances  when  they 
have  not  been  prepared  in  any  way. 

The  wood  which  was  selected  for  trial,  was  generally  of  the  most 
perishable  kind.  In  December,  1838,  several  empty  hogsheads  and 
barrels  made  of  the  best  timber  unimpregnated  and  impregnated  with 
the  pyrolignite  were  placed  together  in  the  dampest  parts  of  the  great 
cellars  of  Bordeaux.  In  August,  1839,  it  was  easy  to  see  that  the 
unimpregnated  tubs  were  already  deeply  stricken,  and  after  from 
two  to  three  years  they  fell  to  pieces  with  the  slightest  force  ;  the 
casks  made  of  the  prepared  wood,  however,  were  as  sound  as  on 
the  first  day  of  the  experiment.* 

M.  Boucherie  concluded  from  his  experiments  instituted  with  a 
view  to  the  settlement  of  the  question,  that  about  ^^'^th  of  the  weight 
of  the  wood  in  its  green  state  of  the  pyrolignite  was  adequate  to 
precipitate  and  render  insoluble  all  the  principles  obnoxious  to  change, 
which  were  contained  in  the  woody  tissue. 

M.  Boucherie,  while  he  regards  the  pyrolignite  of  iron  as  at  once 
the  most  powerful,  and  one  of  the  cheapest  preservatives  of  timber, 
nevertheless  indicates  several  soluble  salts,  which  are  readily  avail- 
able in  consequence  of  their  low  price,  and  also  very  effectual  when 

*  Comptes  Resdas,  t.  ii.  p.  8[«& 


108  PRESERVATION    OF    TIMBER. 

the  wood,  which  they  are  to  preserve,  is  not  kept  constantly  wet. 
Solutions  of  common  salt,  of  chloride  of  lime,  the  mother-water  ol 
salt-marshes,  &c.,  were  all  tried  and  found  useful  :  casks,  the  wood 
of  which  had  been  prepared  with  the  chlorides,  after  having  been 
long  kept  in  very  damp  cellars,  came  out  as  fresh  as  those  which 
had  been  impregnated  with  the  pyrolignite  of  iron  ;  the  flexibility  of 
the  wood  preserved  with  these  alkaline  and  earthy  salts  was  further 
as  CTreat  as  at  the  beginning  of  the  experiment. 

Having  now  come  to  a  conchision  in  regard  to  the  substances 
most  effectual  in  preserving  wood,  the  next  business  was  to  make 
them  penetrate  its  tissue  most  intimately.  Maceration,  M.  Bouche- 
rie  soon  found,  like  his  predecessors  in  the  same  path,  to  be  insuf- 
ficient, the  substances  in  solution  only  penetrating  a  very  little  way. 
He  then  tried  various  processes  of  injection  ;  but  all  inferior  to  that 
imagined  by  M.  Breant^  and  therefore  less  effectual.  He  then  be- 
thought him  of  effecting  the  needful  penetration  of  the  wood  in  the 
green  state,  and  before  it  had  been  sensibly  altered  by  drying  and 
seasoning ;  he  asked  himself  if  the  force  which  determines  the 
ascent  of  the  sap  might  not  be  taken  advantage  of  after  the  tree  was 
cut  down,  as  a  means  of  determining  the  entrance  of  a  solution  of 
pyrolignite  of  iron  1  And  all  his  trials  in  this  direction  answered  his 
expectations  fully.  M.  Boucherie  had,  in  fact,  discovered  a  means 
of  securing  the  penetration  of  the  minutest  pores  of  the  largest  log 
by  a  substance  capable  of  rendering  it  incorruptible.  No  one  before 
M.  Boucherie  thought  of  taking  advantage  of  an  admitted  physiolo- 
gical fact  for  such  a  purpose.  He  announces  the  principle  upon 
which  he  proceeds  in  these  terms  :  "  If  a  tall  tree  be  cut  down  at 
the  proper  season,  and  the  bottom  of  the  trunk  be  then  immersed  in 
a  saline  solution,  weak  or  strong,  the  liquid  is  powerfully  drawn  up 
into  the  tree,  penetrates  its  most  intimate  tissues,  rises  to  its  small- 
est branches,  and  even  to  its  terminal  leaves."* 

In  the  month  of  September,  a  poplar,  upwards  of  90  feet  high  and 
nearly  16  inches  in  diameter,  was  cut,  and  the  bottom  of  its  bole 
plunged  in  a  vessel  containing  a  solution  of  pyrolignite  of  iron  mark- 
ing 8°  of  the  areoQfieter  of  Beaume  ;  in  the  course  of  six  days  it  had 
absorbed  upwards  of  66  gallons  of  the  fluid. 

In  his  first  experiments,  M.  Boucherie  procured  the  needful 
absorption  by  placing  the  bottoms  of  his  trees  in  vessels  containing 
the  solution ;  but  this  mode  of  proceeding  was  obviously  full  of  dif- 
ficulties and  open  to  many  objections  :  the  weight  of  a  green  tree  of 
large  size,  with  the  whole  of  its  top  and  branches,  is  often  enormous, 
and  to  raise  a  mass  of  the  kind  once  down  again  into  the  perpen- 
dicular was  no  easy  task  ;  it  implied  recurrence  to  certain  mechani- 
cal means  which  are  not  always  £t  hand,  and  necessarily  expensive. 
M.  Boucherie,  therefore,  tried  ether  modes  of  making  the  trees 
absorb ;  he  adapted  a  sac  of  imp.jrmeable  material  to  the  bottom  of 
the  trunk  laid  on  the  ground,  and  into  this  sac  he  poured  his  solution, 
«.nd  this  method  answered  very  well.     He  next  took  advantage  of 

♦Ami.  de  Chuuic,  U  !x.\iv.  y.  132< 


TRESERVATION    OF    TIMBER.  109 

one  or  more  of  the  roots  to  effect  the  imbibition.  He  next  bored  a 
hole  into  the  bottom  of  the  trunk,  still  erect ;  and  having  brought 
the  cavity  thus  made  to  communicate  with  a  reservoir,  he  still  suc- 
ceeded. This  last  plan  was  still  further  simplified  in  proceeding  as 
follows  :  the  trunk  of  the  tree  is  pierced  by  an  auger  through  nearly 
the  whole  diameter.  Into  the  auger-hole  thus  made,  a  narrow  saw 
is  passed,  by  working  which  on  either  side,  the  trunk  is  divided  in- 
ternally to  a  very  considerable  extent,  and  the  majority  of  its  sap- 
vessels  are  thus  cut  across  and  made  accessible.  An  impervious 
cloth  is  then  tied  round  the  trunk,  below  the  opening,  and  this  is 
made  to  communicate  with  the  reservoir  of  liquid.* 

M  Boucherie  was  almost  necessarily  led,  in  the  course  of  his  ex- 
periments, to  inquire  whether  the  absorbing  power  of  trees  differed 
at  different  seasons  or  not.  lie  ascertained  by  trials  made  in  the 
months  of  December  and  February,  that  though  in  the  oak,  the  horn- 
beam, and  the  plane,  the  solution  of  pyrolignite  of  iron  always  rises 
several  feet,  and  even  several  yards,  yet  that  in  the  colder  season  of 
the  year,  it  never  rises  so  high  as  it  does  in  summer,  in  spring,  and 
especially  in  autumn,  the  season  in  which  the  power  of  ascent  is 
most  remarkable.  This  conclusion  is  obviously  of  interest  physio- 
logically. It  proves  that  if  winter  be  a  season  of  repose  for  the  sap, 
it  is  not  so  absolutely.  There  is  one  remarkable  exception  to  the 
general  fact  now  announced,  and  this  occurs  among  the  resinous 
trees  that  keep  their  leaves  till  the  spring.  It  has  been  ascertained, 
by  direct  experiment,  that  the  ascent  of  the  sap  continues  through 
the  whole  course  of  the  winter  in  the  cone-bearing  trees,  and  this  to 
such  an  extent,  that  it  is  always  possible  to  impregnate  every  part 
of  their  trunk  by  the  way  of  simple  absorption  at  any  period  of  the 
year.  As  M.  Boucherie  remarks,  this  fact  might  even  have  been 
foreseen  from  the  fresh  and  green  state  of  the  leaves  of  these  trees. 

It  now  became  important,  in  connection  with  the  practical  appli- 
cation of  M.  Boucherie's  views,  to  ascertain  whether  or  not  the 
penetration  was  energetic  in  the  ratio  of  the  vigor  of  the  tree  itself, 
in  proportion  as  it  was  more  numerously  provided  with  branches, 
more  thickly  covered  with  leaves.  Experiment  showed  that  the 
penetration  still  takes  place  after  the  removal  of  the  greater  number 
of  branches,  provided  only  the  leading  bough  or  terminal  crown  be 
left.  A  stem  furnished  with  a  number  of  leafy  branches  continues, 
as  has  been  said,  to  imbibe,  though  separated  from  the  roots  ;  but 
for  how  long  a  time  will  it  continue  to  do  so  ]  This  was  a  capital 
point  to  determine.  At  the  end  of  September,  the  bottom  of  a  pine- 
tree,  about  14  inches  in  diameter,  was  first  put  into  the  solution  48 
hours  after  it  had  been  felled  ;  nevertheless  the  imbibition  was  com- 
plete. In  June  the  same  success  attended  the  experiment  made  on 
a  plane  that  had  been  cut  for  thirty-six  hours.  Still  it  is  certain 
that  the  penetration  takes  place  with  so  much  the  more  energy  as  it 
is  arranged  close  upon  the  time  of  the  felling.  The  power  by  which 
it  is  determined  declines  rapidly  after  the  first  day  is  passed,  and  by 

*  Boucherie,  Ann.  de  Chimie,  t.  Ixxiv.  p.  134.  2e  s6rie 
10 


110  PRESERVATION  OF  TIMBER. 

the  tenth  day  it  is  almost  entirely  gone.  In  favorable  circumstances 
these  ten  days  suffice  to  effect  the  complete  impregnat4nn  of  the 
largest  stem.  In  one  of  his  experiments  upon  a  poplar,  M.  Boucherie 
saw  the  absorbed  liquid  reach  the  height  of  about  95  feet  in  seven 
days. 

In  the  white  woods  it  is  found  that  there  is  an  axis  of  variable 
diameter  in  different  cases  which  escapes  or  rather  which  resists 
impregnation.  In  hard  woods  the  parts  which  are  not  penetrated 
are  the  inner  or  undermost  circles  of  the  heart.  M.  Boucherie,  after 
having  ascertained  these  facts,  explains  them  thus :  in  the  white 
woods,  according  to  the  testimony  of  the  workmen,  the  central  part 
which  resists  the  penetration  is  at  once  the  weakest  and  the  most 
perishable  portion  of  the  log ;  there  is  no  longer  any  circulation,  any 
life  there ;  it  is  dead  wood  interred  in  the  midst  of  the  living  woody 
layers.  This  absence  of  penetration  of  the  woody  tissue  appears, 
on  some  occasions,  elsewhere  than  in  the  centre  of  the  trunk  and 
branches ;  it  presents  itself  under  the  most  various  forms  and  in 
different  parts  of  the  trunk  :  it  appears  to  depend,  as  has  been  said, 
on  the  presence  of  wood  abstracted  from  the  influence  of  vital  phe- 
nomena, and  which,  impenetrable  itself,  presents  a  barrier  or  an  ob- 
stacle to  the  passage  of  the  solution  to  other  parts ;  it  is  thus  that  a 
knot,  or  a  piece  of  rotten  wood,  is  generally  found  as  the  starting 
point  of  the  zones  that  have  escaped  imbibition.  As  to  the  non- 
penetration  of  the  most  central  parts  of  the  heart  of  oak,  elm,  &c., 
M.  Boucherie  views  it  as  affording  unquestionable  proof  of  the  fact 
that  there  the  living  juices  of  the  tree  had  long  ceased  to  circulate. 

The  distinction  generally  drawn  between  the  white  or  soft,  and 
the  perfect  or  hard  wood,  rests  on  the  differences  of  color  presented 
by  a  transverse  section  of  the  trunk.  In  the  oak,  for  example,  the 
external  and  nearly  white  concentric  layers  are  held  as  the  soft  and 
valueless  portion  of  the  log,  and  are  commonly  hewn  away  in  squar- 
ing it ;  the  darker,  more  central  portions  constitute  the  heart-wood, 
the  valuable  timber.  But,  according  to  M.  Boucherie,  the  distinc- 
tion is  different  when  the  fact  of  penetrability  is  taken  as  the  guide, 
and  all  that  portion  of  the  trunk  which  imbibes  is  considered  as 
alburnum,  or  soft  wood,  and  all  that  does  not  imbibe  is  regarded  as 
hard  wood.  The  alburnum  in  this  way  is  so  much  extended  that  it 
may  be  found  constituting  three-fourths  of  the  whole  mass  of  the 
trunk.  Once  introduced,  the  pyrolignite  of  iron,  according  to  M. 
Boucherie,  is  not  only  useful  in  preserving  the  wood,  it  also  in- 
creases the  density  of  the  timber.  Impregnated  with  this  salt  of 
iron,  wood  becomes  so  hard  as  powerfully  to  resist  the  tools  of  the 
oarpenter  and  joiner,  who  even  complain  of  the  increased  difficulty 
with  which  it  is  worked.    - 

Flexibility  and  elasticity  in  timber  are  qualities  in  request  for  cer- 
tain purposes,  particularly  for  ship-building.  The  fir  timber  of  the 
north  of  Europe  is  much  more  prized  than  that  of  the  south,  espe- 
cially for  masting,  on  account  of  its  greater  flexibility  and  elasticity, 
qualities  which  appear  to  depend  in  a  great  measure  en  the  quantity 
of  noisture  retained  ;  to  increase  these  qualities  M.  Boucherie  has 


PRESERVATION  OF  TIMBER.  Ill 

eT«'i>  intioduced  bv  imbibition  a  deliquescent  salt,  such  as  the  muri- 
avit  'jf  li.iJv,  whioh  retains  moisture  powerfully,  as  is  well  known, 
anl  seems  to  have  tna  power  of  giving  a  remarkable  degree  of  sup- 
pleness to  wood.  The  experiments,  contrived  to  show  the  effects 
of  dehquescent  silts,  were  made  upon  deal,  which  is  allowed  to  be 
oncsof  the  most  brittle  woods.  After  having  impregnated  it  with 
concentrated  solutions  it  was  sawed  into  very  thin  veneers,  some  of 
which  I  have  seen  in  the  possession  of  M.  Boueherie,  which  after 
being  strongly  twisted  and  bent  in  various  senses,  immediately  re- 
gained their  original  flatnesa  and  evenness  when  they  were  left 
free. 

Warping,  or  shrinking,  is  occasioned  by  alternate  shrinking  and 
swelling  in  consequence  of  varying  hygrometric  states  of  the  atmo- 
sphere. When  timber  is  worked  before  it  is  thoroughly  seasoned, — 
and  this  is  apt  to  happen  in  regard  to  pieces  of  large  scantling  es- 
pecially— the  shrinking  is  of  course  extremely  conspicuous  when  the 
time  necessary  to  complete  desiccation  has  elapsed.  It  is  this  in- 
convenience which  makes  it  imperative  on  builders  of  all  kinds,  ship- 
builders more  especially,  to  keep  stocks  which  necessarily  absorb 
a  considerable  amount  of  capital.  It  has  long  been  a  question  with 
engineers  to  find  a  remedy  for  this  state  of  things.  Seasoning,  in- 
deed, is  now  effected  somewhat  more  quickly  by  squaring  the  logs 
at  the  time  the  trees  are  cut  down  ;  but  the  loss  of  time  is  still  very 
considerable.  The  mode  of  seasoning  by  the  stove  or  vapor  has 
been  abandoned  as  too  costly. 

After  having  found  that  the  shrinking  and  separation  of  pieces  of 
carpentry  did  not  begin  to  take  place  until  the  timber  was  upon  the 
point  of  losing  the  last  third  of  the  moisture-  which  it  contained  at 
the  time  of  being  cut,  M.  Boueherie  thought  that  to  prevent  all 
warping  and  shrinking  it  would  be  enough  to  retain  this  quantity  of 
water  in  combination  with  the  woody  tissue ;  in  other  words,  to  pre- 
vent complete  desiccation.  Facts  have  proved  the  correctness  of 
this  view.  Pieces  of  vv^ood  kept  at  a  certain  unchanging  degree  of 
moistness  by  means  of  a  deliquescent  salt  infused  into  their  pores, 
do  not  change  their  bulk  or  form,  in  spite  of  extreme  variations  in 
the  hygrometric  state  of  the  air.  Such  pieces  of  wood,  however, 
exhibit  great  differences  in  point  of  weight  under  the  influence  of 
different  circumstances. 

Several  planks  of  great  breadth  and  extremely  thin  were  prepared 
with  chloride  of  lime  and  joined  together ;  some  of  them  were  left 
unpainted,  others  were  painted  on  one  side,  or  on  both  sides ;  after 
the  lapse  of  a  year  these  planks  were  found  not  to  have  shrunk  or 
warped,  while  similar  planks  of  the  same  thickness  and  kind  of 
wood,  but  unprepared,  were  found  to  have  cast  in  an  extraordinary 
way.* 

M.  Boueherie  has  done  more  than  this ;  he  has  not  only  had  it  in 
view  to  preserve  wood  and  to  prevent  it  from  warping,  qualities  so 
desirable, — he  has  made  use  of  the  same  faculty  of  imbibition  to  im- 

*  Boueherie,  op.  cit.  p.  151. 


112  PRESERVATION  OF  TIMBER. 

pregnate  the  wood  with  a  variety  of  beautiful  colors,  and  thus  to 
give  even  the  most  common  kinds  tints  that  will  admit  of  their  being 
used  in  the  construction  of  costly  furniture.  The  pyrolignite  of 
iron  alone  gives  an  agreeable  brown  tint  that  harmonizes  excellently 
with  the  natural  color  of  the  harder  parts  of  so  many  trees  which 
usually  resist  penetration.  By  following  up  the  pyrolignite  with  an 
infusion  of  nutgalls  or  oak-bark,  the  mass  of  the  wood  is  penetrated 
with  ink,  which  presents  a  black,  blue,  or  gray  color,  according  to 
circumstances;  a  solution  of  another  salt  of  iron  succeeded  by  one 
of  prussiate  of  potash  will  cause  a  precipitate  of  prussian  blue  in  the 
wood,  &c. ;  in  short,  by  the  numerous  reactions  of  this  kind  with 
which  chemistry  is  familiar,  a  great  variety  of  colors  may  be  ob- 
tained. 

Among  the  number  of  useful  properties  communicated  to  wood  by 
impregnation  with  saline  solutions,  that  of  being  rendered  little  apt 
for  combustion  ought  not  to  be  omitted.  M.  Gay-Lussac  was  the 
first  who  thought  of  rendering  vegetable  tissues  incombustible  by 
means  of  saline  impregnations.*  By  incombustible,  we  are  not  to 
understand  unalterable  by  a  red  heat ;  for  every  one  must  see  that 
the  protecting  power  of  no  salt  can  extend  so  far  as  this  ;  but  tissues 
which  take  fire  very  readily,  and  burn  with  great  rapidity,  cease 
from  giving  any  flame,  and  merely  smoulder,  after  they  have  been 
impregnated  with  certain  salts ;  they  take  fire  with  difficulty,  go 
out  of  themselves,  become  charred,  and  are  incapable  of  propagating 
fire.  And  this  is  exactly  what  happens  with  wood  which  has  been 
properly  charged  :  it  burns,  and  is  reduced  to  ashes  with  extreme 
slowness,  so  that  two  huts  exactly  alike,  built  one  of  charged  wood, 
and  the  other  of  ordinary  wood,  having  been  set  fire  to  at  the  same 
moment,  the  latter  was  already  burned  to  the  ground,  when  the  in- 
terior of  the  former  was  scarcely  charred. f 

The  ingenious  process  of  impregnating  wood  by  the  way  of  vital 
inspiration  is  not  without  certain  objections.  In  the  first  place,  it 
can  only  be  performed  at  those  periods  of  the  year  when  the  sap  is 
in  motion,  and  the  trees  are  covered  with  their  leaves.  This  time, 
however,  is  limited  to  a  few  months  of  the  year,  and  the  usual  prac- 
tice being  to  fell  timber  in  the  winter,  wont  and  usage  are  opposed 
to  cutting  down  trees  in  the  spring  and  autumn.  To  meet  these 
objections,  M.  Boucherie  engaged  in  new  experiments,  which  led 
him  to  a  means  of  impregnating  timber  at  all  seasons,  in  winter  as 
well  as  spring  and  autumn,  and  in  a  very  short  space  of  time  ;  this 
second  method  is  applicable  to  wood  that  has  already  been  squared 
as  well  as  to  the  round  trunk,  provided  it  has  been  recently  felled. 

To  impregnate  timber  by  this  process,  the  logs  are  placed  verti- 
cally, and  the  upper  extremities  are  fitted  with  an  impermeable  sack 
for  the  reception  of  the  saline  solution  destined  to  charge  them  ;  the 
fluid  enters  from  above,  and  almost  at  the  same  moment  the  sap  is 
Been  to  begin  running  out  below.     There  are  some  woods  which 

♦  Ann.  de  Chimie,  t.  xviii.  p.  21],  2e  sirie. 
t  Idem,  t.  l^xiv.  p.  1.52,  3e  s6rie. 


PRESERVATION    OF    TIMBER.  113 

include  a  large  quantity  of  air  in  their  tissues ;  in  this  case  the  flow 
does  not  go  on  until  this  air  has  heen  expelled  ;  once  begun,  it  goes 
on  without  interruption.  The  operation  is  terminated  when  the 
fluid,  which  drips  from  the  lower  part,  is  of  the  same  nature  as  that 
which  is  entering  above.  In  my  opinion  this  method  must  be  pre- 
ferable to  that  by  aspiration.  In  the  second  mode  of  proceeding,  in 
fact,  we  accomplish  our  object  by  a  true  displacement ;  almost  the 
whole  of  the  sap  is  expelled,  and  the  saline  solution  introduced  has 
only  to  subdue  or  neutralfze  the  very  small  quantity  of  soluble 
organic  matter  which  may  remain  adhering  to  the  woody  tissue. 
By  accomplishing  such  a  displacement  by  means  of  simple  water  w« 
should  undoubtedly  obtain  results  favorable  to  the  preservation  of 
timber,  inasmuch  as  we  should  have  freed  it  from  almost  the  whole 
of  those  matters  which  are  regarded  as  the  most  alterable  them- 
selves, and  the  first  cause  of  rotting  in  timber.  The  rapidity  with 
which  the  fluid  introduced  is  substituted  for  the  sap  which  it  dis- 
places, and  the  quantity  of  this  expelled  sap  which  may  be  readily 
collected,  exceeds  any  thing  that  could  have  been  imagined  before 
making  the  experiment ;  thus  the  trunk  of  a  beech-tree  about  52^ 
feet  in  length  by  33^  inches  in  diameter,  and  consequently  forming 
a  cube  of  somewhat  more  than  29  feet  and  a  half,  gave  in  the  course 
of  twenty-five  hours  upwards  of  330  gallons  of  sap,  which  were  re- 
placed by  about  350  gallons  of  pyroligneous  acid.  The  liquid  which 
penetrates  in  this  way  acts  so  effectually  in  displacing  the  sap,  that 
M.  Boucherie  says  we  can  readily  procure  or  extract  by  its  means 
the  saccharine,  mucilaginous,  resinous,  and  colored  juices  contained 
in  trees.  It  would,  perhaps,  be  possible,  and  I  beg  to  suggest  this 
idea  to  colonial  planters,  to  apply  the  method  of  displacement  to  the 
extraction  of  the  coloring  matters  of  dye-woods.  The  trade  in  dye- 
woods  does  not  extend  beyond  localities  favorably  situated  for  ex- 
portation, so  that  at  a  certain  distance  from  the  shores  of  the  ocean, 
or  the  banks  of  rivers,  it  is  found  absolutely  impossible  to  carry  on 
a  trade,  the  material  of  which  is  so  heavy  and  bulky  as  timber. 
The  greater  number  of  the  coloring  matters  found  in  wood^  being 
soluble,  it  is  possible  to  export  them  in  the  state  of  extract.  Various 
attempts  of  this  kind  have  already  been  made,  and  if  they  have  not 
been  successful,  the  obvious  cause  of  this  lies  in  the  method  which 
has  been  followed,  and  which  has  hitherto  consisted  in  treating  the 
wood  reduced  to  chips  by  means  of  boiling  water,  and  then  reducing 
the  colored  solution  obtained  ;  but  it  is  obvious  that  in  the  remote 
forests  of  America,  or  of  Africa,  where  all  mechanical  means  are 
wanting,  nothing  but  failure  could  attend  upon  such  a  procedure. 
By  the  method  of  M.  Boucherie,  the  main  difficulties  appear  to  be 
got  over  ;  there  is  nothing  more  to  be  done,  in  fact,  than  to  get  the 
trees  into  the  state  of  logs,  and  these  are  generally  readily  trans- 
portable, after  which  one  or  more  evaporating  pans  seem  all  that 
are  further  necessary. 

Dye-woods. — The  greater  number  of  these  woods  belong  to  the 
family  of  leguminosaj  ;  the  principal  kinds  met  with  in  trade  are  : 

I.  Mahogany  wood,  {hmnatoxylon  campechianum,)  of  a  reddish 
10* 


114  SUGAR. 

yellow,  which  becomes  brown  with  age  ;  this  wood,  besides  a  variety 
of  alkaline  and  earthy  salts,  of  volatile  oil  and  unazotized  matter, 
contains  a  particular  coloring  principle,  called  hematine,  discovered 
by  M.  Ciievreul* 

The  mahogany  grows  in  the  hot  intertropical  regions  of  America  ; 
Mexico  and  some  of  the  West  India  islands  export  considerable 
quantities. 

Pernambuco  or  Brazil-wood  is  the  name  given  in  trade  to  the 
trunks  of  several  trees  of  the  genus  Ccesalpinia.  The  Casalpinia 
crista  of  Jamaica,  the  C.  sappan  of  Japan,  the  C.  echinata  of  Santa 
Martha,  afford  kinds  that  are  very  much  prized.  In  point  of  chemi- 
cal composition  Brazil-wood  agrees  with  Campechy  wood  ;  the  col- 
oring matter  which  characterizes  it  has  been  named  Braziline  by  M. 
Chevreul ;  it  is  obtained  in  small  crystals  of  an  orange  color. 

This  wood  comes  to  Europe  in  fagots  of  about  39  inches  in 
length.  Red  Saunders-wood  is  furnished  by  the  Plarocarpus  san- 
talinus ;  it  contains  a  peculiar  dye-stuff,  santaline,  observed  by  M. 
Peltier.f 

To  conclude.,  the  yellow  dye-woods  of  commerce  are  Fustic,  i?/m* 
cotinus,  of  the  family  of  turpentine  trees,  a  native  of  the  south  of 
Europe,  and  the  Cuba  and  Tampico  woods,  which  are  probably  va- 
rieties of  the  Morus  tinctoria. 

OF   SUGAR. 

Sugar  is  met  with  in  almost  every  part  of  vegetables  ;  it  has  been 
found  in  flowers,  in  leaves,  in  stems,  and  in  roots.  It  is  less  abun- 
dant in  seeds  ;  and  it  may  even  be  said  that  the  quantity  of  saccha- 
rine matter  contained  in  vegetables  in  general  is  invariably  diminished 
at  the  period  of  formation  of  the  seed.  Sugar,  consequently,  as  well 
as  starch,  appears  to  contribute  to  the  production  of  the  seed. 

The  very  characteristic  taste  of  sugar  generally  suffices  to  pro- 
claim its  presence ;  nevertheless,  it  would  be  a  great  mistake  did 
we  rely  upon  this  character  alone  for  discovering  the  presence  of 
sugar ;  several  substances  possess  a  very  decided  sweet  taste,  with- 
out being  on  that  account  sugar,  in  the  sense  which  chemists  attach 
Ixi  the  name.  True  sugars,  according  to  chemists,  have  one  properi) 
which  distinguishes  them  from  all  substances  with  which  they  maj 
have,  in  other  respects,  the  greatest  analogy  ;  this  characte;isti» 
property  is  that  of  becoming  changed,  under  the  influence  of  wato 
a  suitable  temperature,  and  contact  with  yeast,  into  alcohol  and  cai 
bonic  acid.  It  is  certain,  nevertheless,  that  certain  bodies  which  d 
not  belong  to  the  chemical  genus,  sugar,  may,  under  the  influence  o 
fermentation,  yield  alcohol.  I  have  already  quoted  starch  as  coming 
under  this  head  ;  but  it  has  been  distinctly  ascertained,  as  1  have  als« 
said,  that  such  substances,  under  the  influence  of  the  ferment  itsell 
are  first  chnnged  into  sugar,  which  subsequently  undergoes  the  vi 
nous  fermentation. 

*  Chimie  appliqu^e  a  la  teinture,  30e  le^on,  p.  88. 

t  Chevreol,  Cheoiistry  applied  to  dyioe,  30tb  Uctor*,  p.  WL 


SUGAR.  It5 

It  is  admitted  at  the  present  time  that  fermentable  su^rs  must  be 
divided  into  two  principal  species,  in  harmony  with  characters  which 
are  most  easily  appreciated.  One  of  these  presents  itself  in  the 
shape  of  hard,  transparent  crystals,  and  is  met  with  in  sufficient 
quantity  to  be  profitably  extracted  from  the  juice  of  the  cane  and  the 
beet,  the  sap  of  the  maple  and  of  certain  palms ;  the  other  is  obtained 
with  some  difficulty  in  the  solid  state,  being  most  frequently  and 
readily  procured  in  the  form  of  sirup  ;  the  taste  of  this  is  less  sweet, 
less  decided  ;  it  exists  in  the  grape  and  the  greater  number  of 
fruits.  The  chemical  characters  of  these  two  kinds  of  sugar,  which 
are  designated  cane-sugar  and  grape-sugar,  are  somewhat  different; 
and  the  elegant  researches  of  M.  Biot  have  shown,  that  from  some 
of  their  physical  properties,  particularly  the  action  of  their  solutions 
upon  polarized  light,  they  cannot  be  regarded  as  constituting  one  and 
the  same  species.  In  the  vegetable  kingdom,  these  two  kinds  of 
sugar  are  frequently  met  with  mixed  ;  and  there  are  certain  chemi- 
cal means  which  enable  us  readily  to  transform  cane-sugar  into 
grape-sugar.  The  inverse  transformation  has  not  yet  been  accom- 
plished ;  but  there  is  nothing  which  leads  us  to  conclude  that  it  is 
impossible ;  and  the  time,  perhaps,  is  not  very  remote  when  the 
sugar  which  is  manufactured  from  potato- starch  may  be  changed 
into  crystallized  sugar,  similar  to  that  which  is  obtained  from  the 
cane. 

Crystallized  sugar.  Cane-sugar  is  readily  obtained  in  large 
transparent  crystals,  which  are  known  under  the  name  of  sugar- 
candy.  Sugar  is  fusible  :  under  the  action  of  a  regulated  tempera- 
ture, it  acquires  a  dark-red  color,  and  passes  into  the  state  of  cara- 
mel ;  a  higher  temperature  effects  its  decomposition.  It  is  much 
less  soluble  in  alcohol  than  in  water ;  highly  concentrated  alcohol, 
indeed,  only  dissolves  an  extremely  small  quantity  of  sugar. 

M.  Peligot's  analysis  of  cane-sugar  shows  it  to  be  composed  of— 

Carbon 42.1 

Hydrogen 6.4 

Oxygen 51.5 

100.0* 

Such  is  the  composition  of  sugar  dried  at  the  temperature  ol  boil- 
ing water  ;  but  the  substance,  like  the  majority  of  organic  matters, 
still  contains  a  certain  proportion  of  constitutional  water,  which  it 
abandons  when  it  combines  with  certain  bases.  Thus  sugar  com- 
bines with  oxide  of  lead,  and  forms  a  true  saccharate,  in  which  the 
sugar,  deprived  of  its  Avater  of  constitution,  plays  the  part  of  an  acid  ; 
this  combination,  which  presents  itself  to  us  under  the  form  of  white 
niammillated  crystals,  analyzed  by  M.  Peligot,  would  indicate  the 
following  as  the  composition  of  anhydrous  sugar — 

Carbon 47-1 

Hydrogen 5.9 

Oxygen 47.0 

100.0 

*  Annales  de  Chimie,  vol.  Ixvili.  p.  134, 3e  t^ii*. 


116  SUGAR. 

Ordinary  sugar,  deprived  of  its  water  of  composition  in  any  othei 
way,  has  the  same  elementary  composition ;  thus  caramel  obtained 
hy  heating  sugar  to  180°  cent.,  (356"  Fahr.,)  until  it  no  longer  loses 
watery  vapor,  has,  according  to  M.  Peligot,  the  composition  of  an- 
hydrous sugar,  such  as  it  is  found  in  combination  with  oxide  of  lead. 

Setting  aside  all  theoretical  considerations,  it  is  obvious  that  to 
have  anhydrous  sugar  reconstituted  ordinary  hydrated  sugar,  it  were 
necessary  to  add  to  100  parts  11.76  of  water,  containing  1.3  hydro- 
gen and  10.46  oxygen  ;  the  111.76  parts  then  contain,  in  element    • 

Carbon 47.1  percent.      42.1  common  sugar 

Hydrogen 7.2        "  6.4  *' 

Oxygen 57.46       "  51.5  " 

111.76  100.0 

Common  sugar  may  therefore  be  viewed  as  composed  of  100  anhy- 
drous sugar,  and  11.8  water. 

The  whole  of  the  sugar  which  comes  from  South  America  and 
the  West  Indies,  and  a  large  proportion  of  that  which  comes  from 
the  East  Indies,  is  extracted  from  the  juice  of  the  sugar-cane. 

In  America  three  principal  varieties  of  sugar-cane  are  cultivated, 
the  Creole,  the  Batavian,  and  the  Otaheitan.  The  Creole  cane  has 
the  leaf  of  a  deep  green,  the  stem  slender,  the  knots  very  close  to- 
gether. This  species,  a  native  of  India,  reached  the  new  world 
after  having  passed  through  Sicily,  the  Canaries,  and  the  West  In- 
dia islands.  The  Batavian  cane  is  indigenous  in  the  island  of  Java  ; 
its  foliage  is  very  broad,  and  has  a  purple  tint ;  the  sap  of  this  vari- 
ety is  much  employed  in  making  rum.  The  Otaheite  cane  is  that 
which  is  most  extensively  grown  at  the  present  time  ;  it  was  intro- 
duced into  the  West  India  islands  and  neighboring  continent  by  Bou 
gainville.  Cook,  and  Bligh,  in  their  several  voyages,  and  is  certainly 
one  of  the  most  important  acquisitions  which  the  agriculture  of  trop- 
ical countries  owes  to  the  voyages  of  naturalists.  This  variety  of 
cane  grows  with  extraordinary  vigor  :  its  stem  is  taller,  thicker,  and 
richer  in  juice  than  that  of  the  other  species.  I  observed  it  along 
the  whole  coast  of  Venezuela,  of  New  Grenada,  and  of  Peru ;  far 
from  having  degenerated  by  its  transplantation  to  the  American  con- 
tinent, it  appears  to  have  preserved  all  its  original  qualities  without 
alteration. 

The  sugar-cane  is  propagated  by  cuttings.  Pieces  of  the  stem 
about  18  or  20  inches  long,  and  having  several  buds  or  eyes,  are 
placed  two  or  three  together  in  holes  a  few  inches  in  depth,  and  are 
covered  with  loose  moist  earth.  From  a  fortnight  to  three  weeks 
are  required  for  the  shoots  to  show  themselves  above  ground.  The 
space  to  be  left  between  each  clump  of  plants  depends  much  on  the 
fertility  of  the  soil  ;  in  the  most  fertile  soils  the  distance  may  be 
about  a  yard,  or  a  little  more ;  and  along  the  rows  the  spaces  may 
be  about  18  inches.  Where  land  is  of  no  great  value  it  is  found 
more  advantageous  to  give  greater  space,  and  so  to  favor  the  access 
of  the  air  and  the  light.  It  is  not  uncommon  to  see  plantations  where 
the  canes  are  spaced  at  distances  of  between  4  and  5  feet.     The 


SXTGAR-CANE.  117 

time  at  which  the  setting  of  the  slips  takes  place  cannot  be  defini- 
tively indicated  ;  it  depends  entirely  upon  the  epoch  at\Ajich  the 
periodical  rains  are  anticipated.  But  in  places  where  irrigation  is 
possible,  the  setting  goes  on  through  all  the  months  of  the  year. 
The  holes  for  the  reception  of  the  slips  are  usually  dug  with  a  hoe, 
and  a  negro  will  make  from  sixty  to  eighty  holes  in  the  course  of  a 
day.  When  the  ground  has  been  previously  ploughed,  as  it  is  in 
some  of  the  West  India  islands,  he  will  make  twice  as  many.  Loose 
rich  soils,  when  they  have  a  certain  moisture,  are  the  best  adapted 
to  the  sugar-cane  ;  it  does  not  thrive  in  an  argillaceous  soil,  which 
drains  with  difficulty.  In  these  moist  soils  the  slips  are  not  laid 
horizontally  and  covered,  bu-t  with  one  end  projecting  a  little  way 
out  of  the  ground.  When  the  young  shoots  are  covered  with  nar- 
row and  opposed  leaves,  watering  is  particularly  advantageous,  and 
the  plants  are  repeatedly  hoed  until  they  have  acquired  sufficient 
vigor  to  choke  noxious  weeds.  About  the  9th  month  after  the  plan- 
tation of  the  slips,  the  shaft  of  the  sugar-cane  begins  to  lose  its 
leaves,  the  most  inferior  falling  first,  the  others  in  succession,  so 
that  when  arrived  at  maturity,  it  only  presents  a  tuft  of  terminal 
leaves.  The  flowering  generally  takes  place  with  the  conclusion 
of  the  year ;  and  the  cane  is  held  sufficiently  ripe  in  from  two  to 
three  months  after  this  epoch,  when  the  stem  has  acquired  a  yellow 
or  straw  color.  The  planters,  however,  are  by  no  means  agreed  as 
to  the  proper  period  of  the  sugar-cane  harvest, — some  even  insist 
upon  cutting  before  the  flowering,  believing  that  the  quantity  of  su- 
gar diminishes  on  the  appearance  of  the  flower.  It  is  unquestiona- 
ble, however,  that  the  period  that  elapses  between  the  planting  and 
the  harvest,  must  vary  with  the  nature  of  the  soil,  and  especially 
with  that  of  the  climate  ;  while  in  some  places  the  cane  may  be  cut 
when  it  is  a  year  old,  doubtless  there  are  others  where  it  requires  to 
stand  from  fifteen  to  sixteen  months.  In  Venezuela,  where  the  Ota- 
heite  cane  is  grown  at  the  level  of  the  sea,  and  where  the  mean  tem- 
perature of  the  year  is  between  81°  and  82°  Fahr.,  the  cane  ripens, 
according  i\,  Dolonel  Codazzi,  in  eleven  months.  In  districts  at 
greater  elevations  under  the  same  parallels  of  latitude,  where  the 
climate  is  of  course  not  so  hot,  the  cane  requires  a  longer  time  to 
come  to  maturity  ;  where  the  mean  temperature  is  about  78"  Fahr., 
twelve  months  are  required  ;  where  it  is  about  74°  Fahr.,  fourteen 
months  become  necessary ;  and  where  it  is  no  more  than  about  67° 
Fahr.,  sixteen  months  are  requisite.*  The  Otaheite  cane  grows  to 
very  different  heights  ;  in  very  favorable  circumstances  it  will  reach 
a  height  of  16  feet  and  upw^ards,  but  its  general  height  may  be  stated 
at  from  9h  to  10^  feet.  Great  cane,  plantations  are  divided  into 
squares  of  from  100  to  120  yards  on  the  side,  each  of  which  coming 
to  maturity  in  succession,  the  labor  is  easily  performed,  both  in  re- 
gard to  field-work  and  the  manufacture  of  the  sugar. 

The  cane  is  cut  close  to  the  root,  and  before  being  carried  to  the 
mill,  the  tey rainal  tuft  of  leaves  is  struck  oflf.     The.^^e  h-^ads  in  the 

*  Codazzi,  Geography  of  Venezuela,  p.  141. 


118  SUGAR-CANE. 

green  state  afford  excellent  food  for  horses  and  cattle ;  when  dry 
they  are  used  for  thatching-  houses.  After  the  first  cuting,  fresh 
sprouts  arise,  which  require  no  other  attention  than  hoeing.  In  good 
soils  one  planting  will  yield  five  or  six  harvests  by  successive 
shoots  ;  but  I  have  heard  planters  affirm,  that  the  produce  in  sugar 
diminishes  from  year  to  year.  In  Venezuela,  cane-pieces  are  re- 
planted every  five  or  six  years. 

The  cane  with  its  top  struck  off  is  carried  to  the  mill,  where  the 
juice  is  expressed,  and  the  stems,  which  are  spoken  of  under  the 
name  of  trash,  are  dried  and  used  as  fuel. 

The  expressed  juice  contains  crystallizable  sugar,  an  azotized 
substance  analogous  to  albumen,  and  some  saline  matters  dissolved 
in  a  large  quantity  of  water,  which  is  dissipated  by  boiling,  and  the 
sugar  finally  won  by  crystallization.  The  manufacturing  process  is 
conducted  with  very  different  degrees  of  perfection  in  different 
places.  In  some  the  produce  is  obtained  almost  without  admixture 
of  molasses,  in  others  the  quantity  of  this  article  which  drains  away 
from  the  sugar  is  very  large.  It  is  now  generally  agreed  that  mo- 
lasses proceeds  in  great  part  from  imperfections  in  the  manufacturing 
processes  employed,  especially  to  changes  which  the  sugar  under- 
goes in  the  course  of  its  concentration  by  boiling  at  a  high  tempera- 
ture. By  the  employment  of  what  are  called  vacuum  pans  of  vari- 
ous construction — pans  from  which  the  pressure  of  the  atmosphere 
is  removed  either  by  the  air-pump,  or  the  condensation  of  the  vapor 
as  fast  as  it  is  formed,  rapid  evaporation  is  effected  at  a  temperature 
much  below  that  of  boiling  water,  by  which  it  is  found  that  the  rela- 
tive quantity  of  sugar  to  that  of  molasses  is  greatly  increased.  I 
was  long  believed,  indeed,  and  that  on  the  authority  of  the  first 
chemists,  that  there  were  two  kinds  of  sugar  contained  in  the  sugar- 
cane, one  crystallizable,  the  other  uncrystallizable,  and  constituting 
the  molasses  or  treacle.  The  researches  of  M.  Peligot*  have 
shown  definitively  that  this  conclusion  is  erroneous,  that  the  cane  con- 
tains no  sugar  that  is  not  crystallizable,  and  that  the  pre-existence 
of  uncrystallizable  sugar  or  molasses  is  entirely  chimerical.  M. 
Plague  had  indeed  come  to  the  same  conclusion  some  considerable 
time  ago — as  far  back  as  1826  ;  but  his  labors  were  not  made  known 
by  publication  till  1840.  M.  Casaseca,  professor  of  chemistry  at 
Havana,  has  very  lately  confirmed  these  conclusions,  so  important 
for  the  sugar  husbandry  of  the  world. f  The  composition  of  the 
juice  of  the  sugar-cane  is  therefore  less  complex  than  it  was  once 
believed  to  be  ;  making  abstraction  of  very  minute  quantities  of  an 
albuminous  azotized  substance,  of  several  salts  and  a  little  silica, 
substances  which  altogether  do  not  amount  to  more  than  two  or 
three  hundredths,  cane  juice  may  be  said  to  consist  of  water  and  of 
crystallizable  sugar  in  the  proportion  of  from  17  to  20  per  cent  | 
The  Otaheite  cane  analyzed  by  M.  Peligot  actually  yielded  : 

■^  Ann.  Mdiivimcs  et  Coloniales,  Aug.  1842. 

I  Vide  Comptes  Rendus,  1844.  %  Peligot,  op  tit 


SUGAR-CANE.  119 

Water 72.1 

Woody  matter 9.9 

Soluble  matter  (sugar) 18.0 

mo" 

Ti  is  conclusion  was  verified  by  M.  Dupuy  at  Guadaloupe  in  1841, 
who,  operating  on  the  spot,  found  the  composition  to  be  as  follows  • 

Water 72.0 

Woody  matter 9.8 

Soluble  matter  (sugar) 17.8 

Salts 0.4 

100.0 

The  analyses  of  the  Creole  cane  made  by  M.  Casaseca  at  Havana 
appear  to  indicate  a  larger  quantity  of  woody  fibre  : 

Water.   65.9 

Wood 16.14 

Sugar 17.7 

100.0 

The  quantity  of  sugar  yielded  by  the  cane,  differs  considerably. 
M.  Codazzi  assigns  6  and  15  per  cent,  as  the  extremes,  and  7^  per 
cent,  as  the  mean.  M.  Dupuy  gives  7.1  per  cent,  as  the  average. 
The  quantity  is,  of  course,  first  and  most  intimately  connected  with 
the  quantity  of  juice  obtained.  But  the  produce  of  juice  is  extremely 
variable.  In  Guadaloupe,  the  juice  varies  between  56  and  62  per 
cent,  of  the  cane  subjected  to  pressure.  The  generality  of  mills  do 
not,  in  fact,  enable  us  to  obtain  more  than  about  56  per  cent.  At 
New  Orleans  the  usual  quantity  obtained  is  said  to  be  50,  and  in 
Cayenne  only  36  per  cent.  At  Havana,  according  to  M.  Casa- 
seca, the  riband  cane  yields  45,  the  crystalline  35,  and  the  Otaheitan 
56  per  cent,  of  juice. 

The  Otaheite  cane  was  examined  by  M.  Peligot,  under  a  variety 
of  circumstances  of  age,  growth,  part  of  plant,  &c.  &c.  The  fol- 
lowing table  contains  the  condensed  results  of  his  experiments  : 


First  shoots ■ 

Second  do.  from  original  sprouts  • 
Third    do.  from  second        do. 
Fourth  do.  from  third  do. 

Inferiorpart  of  cane 

Middle  part  of    do 

Superior  part  of  do.   

Knots 

Cane  of  eight  months 

Cane  of  ten  months 


Water. 

Soluble  mat- 
ters (suffar.) 

Woody  fibre. 

73.4 

17.2 

8.9 

71.7 

17.8 

10.5 

71.6 

16.4 

12-0 

73.0 

16.8 

10.2 

73.7 

15.. 5 

10.8 

72.6 

16.5 

10-9 

72.8 

15.5 

11.7 

70.8 

12.0 

17.2 

73.9 

18.2 

7.9 

72.3 

18.5 

9.2 

It  would  therefore  appear,  making  exception  always  of  the  knots 
which  occur  in  the  course  of  a  cane,  that  the  composition  of  the 
plant  in  its  various  states  and  conditions,  is  almost  identical.  M. 
Peligot's  important  paper,  while  it  informs  us  of  the  average  com- 
position of  the  Otaheite  cane,  satisfies  us  that  the  gummy  and  mu 


120  SUGAR-CANK. 

cilaginous  substances  and  the  uncrystallizable  sugar,  tie  existence 
of  which  was  held  as  demonstrated,  are,  in  fact,  nowise  constituents 
of  the  sugar-cane.  Whence  we  may  conclude,  with  M.  Peligot,  that 
every  drop  of  molasses  which  drains  from  the  sugar  is  the  produce 
of  the  manufacture ;  an  opinion  to  which  I  assent  the  more  readily 
from  having  myself  seen  oftener  than  once  the  juice  of  the  cane 
yield  nothing  but  crystallizable  sugar  These  analyses  further  de- 
monstrate, more  powerfully  than  could  any  discussion,  the  imperfec- 
tion of  the  processes  usually  followed  in  manufacturing  sugar.  They 
prove,  in  fact,  that  in  the  mill  rather  more  than  a  third  of  the  whole 
juice  contained  in  the  cane  is  left  in  the  trash.  This  loss  might  be 
considerably  diminished  were  more  perfect  pressure  employed  in 
extracting  the  juice.  But  it  appears  that  the  planters  are  indisposed 
to  crush  the  trash  too  much,  as  by  this  it  is  rendered  less  fit  for  fuel, 
a  considerable  quantity  of  which,  by  the  present  mode  of  manufac- 
ture, is  indispensable.  M.  Dupree,  however,  says  that  by  insisting 
on  obtaining  from  65  to  66  per  cent,  of  juice  in  all  cases,  the  trash  is 
still  left  with  all  its  value  as  a  combustible.  The  trash  on  coming 
from  the  mill  appears  quite  dry.  I  have  seen  some  which,  after 
having  been  pressed  twice  consecutively,  looked  as  if  it  were  im- 
possible by  any  further  amount  of  pressure  to  express  more  liquid. 
Nevertheless,  it  was  enough  to  taste  this  pressed  cane,  to  be  satis- 
fied that  it  still  contained  a  considerable  quantity  of  sugar.  To 
procure  this  without  using  more  powerful  machinery,  M.  Peligot 
proposed  to  steep  the  trash  in  water,  and  to  press  it  a  second  time. 
By  this  means  a  weak  juice  is  obtained,  which,  added  to  the  first 
pressings,  raises  the  produce  of  sugar  from  7  to  10  per  cent,  upon 
the  whole  amount  of  cane  employed.  By  following  this  process, 
suggested  by  theory,  upon  the  great  scale,  M.  Dupree  has  succeeded 
in  obtaining  |th  more  than  the  usual  quantity  of  sugar  without  ma- 
king any  change  in  his  apparatus,  and  without  finding  the  trash  too 
much  shaken  to  be  burned  under  his  coppers.*  In  some  circum- 
stances the  increase  in  the  quantity  of  juice  which  this  procedure 
implies,  might  be  found  an  objection  on  account  of  the  larger  quan- 
tity of  fuel  required  for  its  evaporation  ;  but  wherever  a  supply  of 
wood  is  to  be  had,  M.  Peligot's  method  ought  undoubtedly  to  be  ap- 
plied. 

The  very  dissimilar  quantities  of  crystallizable  sugar  obtained  from 
canes,  which  as  we  have  seen  all  contain  very  nearly  the  same  quan- 
tity of  this  substance,  prove  that  the  processes  of  concentration  and 
purification  of  the  sap  also  contribute  to  the  loss  which  has  been  in- 
dicated. M.  Peligot  has  pointed  out  several  causes  which  concur  to 
deteriorate  sugar  ;  among  the  number:  1.  A  viscous  fermentation 
which  renders  the  sap  thi(;k  and  stringy,  like  mucilage,  by  which 
the  boiling  becomes  diflicult  and  the  crystallization  of  the  sugar 
which  has  escaped  change,  is  rendered  imperfect.  2.  An  acidity 
which  takes  place  when  the  juice  is  not  run  at  once  into  the  coppers 
and  boiled,  an  acidity  which  requires  the  addition  of  lime  to  destroy 

*  Peligot,  Maritime  and  Colonial  Annals,  August,  1848. 


SUGAR-CANE.  121 

to  prevent  it.  The  alkaline  iarth,  as  I  have  had  occasion  tc  say, 
•  by  no  means  indispensable  ;  its  utility  under  ordinary  circunistan- 
ces  is  probably  confined  to  assisting  the  defecation  by  forming  an  in- 
soluble precipitate  with  some  of  the  organic  substances  which  are 
always  met  with  in  small  quantities  in  cane  juice ;  perhaps  also  to 
making  an  earthy  soap  with  the  fatty  matters  which  adhere  to  the 
cane  and  are  expressed  in  the  crushing.  When  lime  is  added,  to 
correct  acidity,  it  forms  an  acetate  or  a  lactate,  salts  which  are  pe- 
culiarly soluble,  uncrystallizable,  and  which  necessarily  retain  a 
quantity  of  sugar  in  the  sirupy  state.  3.  The  presence  of  certain 
mineral  salts  in  the  cane.  Common  salt,  for  instance,  in  combining 
with  sugar  forms  a  deliquescent  compound,  in  which  one  part  of  salt 
is  united  with  six  parts  of  sugar ;  such  a  compound  as  this  of  course 
renders  a  large  quantity  of  sirup  indisposed  to  crystallize.  It  is 
therefore  impossible  to  be  too  cautious,  according  to  M.  Peligot,  in 
the  choice  of  manure  for  a  cane-field  ;  that  which  contains  any  com- 
mon salt  must  needs  be  injurious  in  one  way,  however  advantageous 
it  may  be  in  another.  The  entire  absence  of  this  salt  in  the  soil  of 
plantations  which  are  very  remote  from  the  sea  shore  is  perhaps  one 
of  the  causes  which  increases  the  quantity  of  sugar  obtained  from 
the  crop,  and  makes  it  more  easily  manufactured  in  such  districts. 

M.  Codazzi  reckons  the  quantity  of  white  sugar  produced  by  a 
hectare  of  land,  (2.473  acres,)  planted  with  the  Otaheite  cane  in  the 
province  of  Caraccas,  at  1875  kilogrammes,  or  36  cwt.  3  qrs.  9  lbs. 
avoir.  ;  which  is  at  the  rate  of  15  cwt.  1  or.  10  lbs.  per  acre. 
Taking  7|  per  cent,  as  the  average  quantity  jf  sugar  obtained,  the 
weight  of  cane  brought  to  the  mill  must  obviously  have  amounted  to 
19134  kilog.  or  18  tons,  15  cwt.  3  qrs.  10  lbs. ;  or  7  tons,  11  cwt. 
3  qrs.  25  lbs.  per  acre.  Assuming  the  average  composition  of  the 
plant  to  be — 

Wood  (dry) 11.0 

Sugar  (minimum) 15.5 

Water .73.5 

100.0 

One  acre  of  land  will  consequently  yield  a  crop  of — 

Tons.  Cwt.  Qrs.  Lb* 

Wood  (dry)   0  16  2  24 

Sugar 1  3  2  6 

Water  -5  i^  ^  I? 

7  11  3  25 

The  trash  of  the  sugar-cane  undergoes  rapid  fermentation  :  it  soon 
exhales  a  distinct  smell  of  vinegar,  and  almost  the  whole  of  the 
sugar  which  is  left  in  it  is  destroyed. 

BEET-ROOT  SUGAR. 

The  presence  of  sugar  in  the  beet  was  observed  by  Margraff;  and 
Achard  of  Berlin  by  and  by  attempted  the  extraction  of  this  sugar 
on  the  large  scale  ;  but  it  was  only  during  the  period  of  the  conti- 
nental system  that  the  manufacture  of  sugar  from  the  beet  acquired 

11 


122  BEET  ANJ>  BEET-SUGAR. 

such  perfection  in  France  as  made  it  profitable.  The  beet  so  geii' 
eraliy  cultivated  at  the  present  time  is  derived,  according  to  Thaer, 
from  the  Beta  vulgaris.  The  two  principal  varieties  of  this  root  are 
the  red  beet,  which  has  been  grown  for  a  very  long  time  in  kitchen 
gardens,  and  the  white  beet.  Between  these  two  extremes  there 
are  numerous  varieties  having  a  flesh  color  of  various  intensity,  a 
yellow  tint,  &c.  The  seeds  of  the  same  plant  in  fact  frequently 
produce  varieties  of  decidedly  diiferent  shades  of  color  ;  the  red  and 
the  white  beet,  however,  appear  to  be  the  most  constant ;  and  Thaer  has 
said  that  the  intermediate  varieties  are  crosses  between  them. 

The  field  beet  has  a  large  root  which  grows  in  great  part  above 
the  ground  ;  it  is  a  very  hardy  plant,  which  has  been  cultivated  for 
a  very  long  time  in  various  parts  of  the  continent  as  food  for  cattle, 
and  is  now  also  very  common  in  England.  The  root,  which  has 
hitherto  been  preferred  for  the  manufacture  of  sugar,  is  conical,  of  a 
rose  color  without,  and  its  concentric  external  layers  are  also  color- 
ed ;  but  it  appears  that  the  white  beet  of  Silesia  is  the  more  pro- 
ductive. The  beet  thrives  in  almost  all  kinds  of  soil,  provided  only 
they  be  sufficiently  manured.  In  Alsace  it  succeeds  in  light,  and  in 
strong  argillaceous  soils  indifferently.  Another  precious  quality  which 
this  root  possesses  is  that  of  succeeding  in  the  most  dissimilar  cli- 
mates ;  it  is  grown  to  purpose  both  in  the  north  and  in  the  south  of 
France. 

The  beet  is  sown  at  once  in  the  field,  or  in  a  bed  and  transplanted  ; 
the  latter  method  appears  now  to  obtain  a  decided  preference,  inasmuch 
as  it  leaves  plenty  of  time  for  the  preparation  of  the  soil,  and  espe- 
cially for  accumulating  and  carrying  out  manure. 

In  a  piece  of  ground  well  broken  up  by  delving  or  ploughing,  and 
highly  manured,  which  need  not  be  of  greater  extent  than  {-'jyth  of 
the  entire  surface  to  be  planted,  the  seed  is  sown  in  lines  or  drills 
as  soon  as  the  spring  frosts  are  no  longer  to  be  apprehended.  The 
transplanting  in  the  east  of  France  takes  place  about  the  middle  of 
May,  and  even  in  the  beginning  of  June.  The  plants  are  generally 
set  about  15  inches  apart.  In  the  north  the  beet  harvest  does  not 
begin  before  the  end  of  September,  and  generally  ends  in  the  course 
of  the  month  of  October.  The  gathering  is  delayed  as  long  as 
possible,  inasmuch  as  the  roots  increase  visibly  to  the  very  end  of 
the  season.  But  gathering  the  beet  at  a  very  late  period  in  those 
countries  where  the  winter  seed  has  to  follow  this  crop,  is  attended 
with  more  than  one  disadvantage.  Without  speaking  of  the  difficul- 
ties that  are  incidental  to  wet  seasons,  a  late  seed-time  is  generally 
unfavorable  for  wheat.  To  meet  this  difficulty,  I  have  been  accuS' 
tomed  for  some  time  to  take  up  my  crop  of  beet  at  the  period  when 
it  became  necessary  to  prepare  the  land  for  winter  seed,  that  is  to 
say,  more  than  a  month  before  the  general  harvest  of  the  root.  In 
doing  so  I  relied  upon  the  interesting  fact  ascertained  by  M.  Peligot 
in  the  course  of  his  chemical  inquiries,  viz  :  that  the  composition  of 
the  beet  is  identical  at  every  age.  In  this  premature  or  anticipated 
beet  harvest,  a  less  weight  of  root  is  of  course  gathered  than  would 
have  been  obtained  at  a  later  period ;  but  the  nutritious  powers  of 


BEET   AND   BEET-SUGAR.  /  123 

these  beet  roots  are  the  same  as  they  would  ever  have  been.  The 
grand  questions  to  be  determined  were,  whether  the  roots  would 
keep  or  not,  and  whether  the  cattle  would  eat  them  from  the  pile  as 
freely  as  from  the  field.  All  this  was  ascertained  in  the  course  of 
the  winter :  the  beet  kept  perfectly,  the  cattle  ate  it  as  freely  as  ever. 
The  procedure  to  be  adopted  therefore  to  secure  a  crop  of  beet  of 
average  weight,  storing  nevertheless  some  considerable  time  before 
the  usual  period,  is  simply  to  transplant  somewhat  more  closely,  and 
to  put  less  space  between  the  drills.  If  experience  decides  in  favor 
of  this  method,  the  sole  inconvenience  which  attends  the  cultivation 
of  the  beet  in  a  freshly  manured  soil,  and  as  the  first  crop  in  the 
rotation,  that,  namely,  of  causing  a  late  and  unfavorable  seed-time  for 
winter  corn,  will  be  completely  got  over. 

The  beet  which  grows  above  the  ground  is  best  gathered  with  the 
hand  ;  kinds  that  grow  under  ground  require  to  be  loosened  by  run- 
ning a  plough  along  the  drill,  &c.  In  Alsace  it  is  the  custom  to  take 
away  the  leaves,  and  to  trim  the  roots  upon  the  ground  ;  the  refuse 
thus  obtained  constitutes  a  considerable  mass  of  manure,  which  it  is 
well  to  plough  in  immediately. 

To  extract  the  sugar  of  the  beet  the  plant  is  washed  and  rasped, 
and  the  pulp  is  then  subjected  to  the  action  of  a  powerful  press. 
Like  the  juice  of  the  cane,  the  juice  of  the  beet  speedily  undergoes 
a  change  ;  it  is  therefore  immediately  heated  to  70°  cent,  or  158°Fahr , 
and  a  little  lime  is  mixed  with  it  to  neutralize  acid  and  favor  the  clarifi- 
cation, by  combining  with  albumen.  The  liquor  is  skimmed,  and  in  the 
course  of  an  hour  becomes  quite  limpid,  and  of  a  pale  yellow  color. 
The  liquor  is  then  run  upon  a  filter  containing  animal  charcoal,  and 
from  that  is  transferred  to  a  boiler  where  it  is  properly  reduced,  the 
process  being  in  all  respects  the  same  as  in  the  manufacture  of  cane 
sugar.  '' 

In  France,  the  produce  of  each  110  lbs.  weight  of  beet  is  estimated 
at  4.5(5,  or  somewhat  more  than  4j  lbs.  of  white  sugar.  The  amount 
of  loss  in  the  manufacture  may  be  conceived  from  the  actual  compo- 
sition of  the  beet,  which,  by  the  process  followed  by  M.  Peligot,* 
and  which  consists  essentially  in  drying  a  certain  weight  of  the  root, 
cut  into  thin  slices,  and  then  exhausting  the  matter  with  boiling 
alcohol  of  moderate  density,  appears  to  contain  from  4  or  5,  up  to  9, 
10,  11,  and  even  nearly  12  per  cent,  of  sugar.  This  analysis  of  M. 
Peligot  has  been  confirmed  by  the  experiments  of  M.  Braconnot,t 
who  found  the  white  beet  of  Silesia  to  have  a  very  complex  compo- 
sition, comprising  as  many  as  twenty-one  different  ingredients,  among 
the  number  crystallizable  sugar,  albumen,  woody  matter,  phos- 
phate of  magnesia,  phosphate  of  lime,  oxalate  of  potash,  and  oxalate 
of  lime,  oxide  of  iron,  an  ammoniacal  salt  in  small  ({uantity,  &c. 
On  an  average,  the  analysis  of  M.  Peligot  would  lead  us  to  conclude 
tnat  the  beet  ^,ontained  in  one  hundred  parts — 

*  Recherches  sur  I'analyse  de  la  betterave  a  sucre. 
t  Annales  de  Chimie,  vol.  Ixxii.  p.  442,  2d.  series. 


124  BEET  AND  BEET- SUGAR. 


Water  87 

Matter  soluble  in  water  (sugar) 8 

Insoluble  substances,  (woody  tissue) 5 

"loo 

from  which  it  appears  that  no  more  than  about  fths  of  the  sugaf 
contained  in  the  heet-root  is  extracted.  As  in  crushing  the  cane,  so 
in  squeezing  the  rasped  pulp  of  the  beet,  a  part  of  the  loss  is  owing 
to  a  certain  quantity  of  sugar  being  left  in  the  expressed  pulp.  In 
fact,  with  the  presses  generally  in  use,  while  from  60  to  70  per  cent, 
of  juice  is  obtained,  the  root  actually  contains  95  per  cent.  The 
loss  here,  however,  is  of  less  consequence  than  it  is  in  the  cane-,  the 
trash  of  which  is  used  for  fuel,  while  the  pulp  of  the  beet  serves  as 
food  for  cattle.  The  pulp,  indeed,  is  found  to  possess  very  nearly 
the  same  amount  of  nutritive  power  as  the  root  which  produced  it. 

One  of  the  considerations  which  is  perhaps  of  highest  importance 
in  connection  with  the  production  of  sugar  from  the  beet,  is  inherent 
in  lh(5  difficulty  of  preserving  the  root  after  it  is  full-grown.  Gather- 
ed at  the  end  of  autumn  the  root  suffers  no  less  from  severe  frost, 
than  it  does  from  mild  open  weather  :  frost  destroys  its  organiza- 
tion, and  in  mild  winters  vegetation  continues  at  the  expense  of  the 
sugary  principle,  which  had  been  formed  during  the  growth.  If  the 
beet  actually  contains  at  every  period  of  its  existence  the  same 
quantity  of  sugar  with  reference  to  its  weight,  there  would  probably 
be  a  great  advantage  in  not  waiting  for  the  period  of  complete  ma- 
turity, by  sowing  somewhat  thicker  than  wont ;  any  difference  of 
weight  would  probably  be  made  up,  and  then  there  would  be  no  risk 
of  loss  from  keeping. 

The  quantity  of  beet  gathered  from  a  given  extent  of  land  neces- 
sarily varies  with  the  soil,  the  pains  bestowed  upon  the  crop,  and 
the  quantity  of  manure  that  has  been  used  ;  the  following  are  a  few 
particulars  from  official  documents  : 

PRODUCE  PER  ACRE. 
Ton.        Cwt.        Qra.        Lba. 

PasdeCalais 12         9         1        19 

Department  of  the  North    12       10         2       25 

Department  of  Cher  15         1       39 

but  in  other  departments  the  produce  is  considerably  smaller,  so  that 
the  average  for  the  whole  country  has  been  estimated  at  not  more 
that  10  tons  9  cwt.  1  qr.  13  lbs.  per  acre;  an  average  which  ap- 
proaches very  closely  to  that  which  I  have  obtained  from  my  own 
farm  at  Bechelbronn,  calculated  during  a  period  of  seven  years. 

Assuming  4~7fths  lbs.  of  sugar  to  be  obtained  from  every  110  lbs. 
of  beet,  the  produce  in  sugar  from  an  English  acre  in  the  course  of 
seven  months  will  amount  in  the  present  state  of  things  to  9  cwt.  2 
qrs.  and  7  lbs.  By  way  of  comparison  I  shall  here  remind  the 
reader  that  an  English  acre  of  land  laid  out  in  Otaheite  sugar-cane 
yields  in  the  course  of  about  fourteen  months,  15  cwt.  1  qr.  10  lbs. 
I  find  from  my  accounts  for  1841,  that  to  manage  an  English  acre 
of  land  under  beet-root  in  Alsace,  45.6  days  ojf  a  man,  and   14.1 


BEET  AND  BEET-STTGAR.  125 

days  of  a  horse  was  the  amount  of  labor  expended.  In  a  document 
upon  the  sugar  plantations  of  Guadaloupe  which  I  have  seen,  it  is 
stated  that  a  domain  of  150  hectares,  or  370  acres,  is  worked  by  150 
negroes,  which,  reckoning  the  time  that  the  crop  is  on  the  ground 
at  fourteen  months,  would  bring  the  number  of  days  labor  by  a  man,, 
to  171.8  per  English  acre.  Such  an  expenditure  of  labor  must  in 
the  nature  of  things  absorb  the  greater  part  of  the  profits  ;  and, 
indeed,  in  a  commission  of  inquiry  into  the  laws  connected  with  the 
sugar  trade,  it  was  shown  in  reference  to  the  plantation  in  ques- 
tion, that  the  cost  of  cultivation  and  manufacture  was  equal  to  the 
value  of  the  produce.  Still  the  cane  presents  one  considerable 
advantage  over  the  beet,  that,  namely,  of  furnishing  the  fuel 
necessary  to  the  boiling,  an  advantage  which  will  be  better  under- 
stood, when  it  is  known  that  in  the  manufacture  of  every  110  lbs. 
weight  of  beet  sugar,  the  consumption  of  coal  amounts  to  22  lbs. 

In  countries  where  sugar  is  cheap,  it  becomes  an  ordinary  article 
of  diet;  in  the  public  market-places  of  the  great  towns  of  South 
America,  one  of  the  rations  commonly  exposed  for  sale  consists  of 
brown  sugar  and  cheese.  M.  Codazzi  estimates  the  quantity  of 
sugar  consumed  by  each  inhabitant  of  Venezuela  at  110  lbs.  In 
England  it  amounts  to  about  22  lbs.  ;  in  Ireland,  to  no  more  than 
4  lbs.  and  ^ths ;  in  Holland  it  is  15yV  lbs. ;  in  France  it  is  8-^^  lbs. ; 
in  Italy,  2^  lbs.  ;  and  in  Russia,  but  ly^j^  lb.  per  head. 

Maple  sugar.  (Acer  saccharinum.)  The  maple  is  very  common 
in  the  east  of  the  United  States  of  America.  The  tree  is  occa- 
sionally met  with  in  clumps  of  several  acres  in  extent,  but  it  is 
more  commonly  found  dispersed  in  the  forest,  growing  among  pines, 
poplars,  ashes,  &c.  The  tree  grows  particularly  in  rich  soils,  and 
attains  the  height  of  the  oak ;  the  trunk  being  often  more  than  three 
feet  in  diameter.  The  maple  becomes  covered  with  flowers  in  the 
spring  before  the  appearance  of  the  leaves.  It  is  supposed  to  be  in 
its  prime  at  the  age  of  about  twenty  years.  The  sap  of  the  maple 
is  obtained  by  piercing  the  trunk  to  the  depth  of  from  six  to  ten 
inches.  A  piece  of  wood  to  serve  as  a  gutter  is  placed  in  the  hole, 
and  the  sap  is  received  in  a  vessel  placed  underneath.  It  is  usual 
to  pierce  the  tree  first  on  the  side  that  is  towards  the  south ;  when 
the  flow  of  sap  begins  to  lessen,  it  is  tapped  upon  the  north  side. 
The  best  season  for  making  maple  sugar  is  the  beginning  of  spring, 
February,  March,  and  April ;  the  sap  continues  to  flow  during  five 
or  six  weeks.  The  quantity  of  sap  obtained  is  found  to  be  largest 
when  the  days  are  hot  and  the  nights  cold ;  the  quantity  collected 
in  the  course  of  twenty-four  hours  will  vary  from  about  half  a  pint 
to  thirty  pints  and  more  ;  the  temperature  of  the  air  has  the  most 
marked  influence  upon  the  flow  of  the  sap ;  it  ceases  completely, 
for  instance,  in  those  nights  when  it  freezes  after  a  very  hot  day. 

The  maple  does  not  appear  to  s'iffer  from  reiterated  perforation  ; 
trees  are  mentioned  which  were  still  flourishing  after  having  yielded 
sugar  for  forty-two  consecutive  years.  In  certain  cases,  which, 
however,  must  be  held  as  exceptions  to  the  rule,  as  many  as  183 
pints  of  sap  have  been  tapped  from  a  maple  ia  the  course  of  twenty 


126  PALM-SFGAR. 

four  hours,  which  j^ielded  4j\  lbs.  of  crystallized  sugar.  A  maple 
of  ordinary  dimensions,  in  a  good  year,  will  yield,  on  an  average, 
about  198  pints  of  sap,  producing  5^  lbs.  of  sugar.  The  sap  of  the 
maple  must  therefore  contain  about  2.2  per  cent,  of  its  weight  of 
marketable  sugar.  It  has  been  found,  that  with  care  and  attention 
the  maple  becomes  more  productive  ;  maples  around  which  other 
forest  trees  have  been  felled,  or  which  have  been  transplanted  into 
gardens,  yield  a  sap  which  is  not  only  more  abundant,  but  also 
richer  in  sugar,  which,  in  fact,  contains  about  three  per  cent,  of 
sugar. 

The  manufacture  of  maple  sugar  presents  no  peculiarity ;  pre 
cisely  the  same  process  is  followed  as  in  the  case  of  the  cane  and 
beet.  Unless  very  speedily  boiled  down,  the  sap  ferments,  and 
undergoes  change ;  in  some  parts  of  the  United  States,  indeed,  a 
vinous  liquor  is  made  of  the  sap,  by  allowing  it  to  run  into  sponta- 
neous fermentation. 

PALM  SUGAR. 

The  palm  which  in  the  southern  parts  of  India  furnishes  crystal- 
lized sugar  in  large  quantity,  is  the  cleophora  of  Gaertner,  and 
reaches  a  height  of  about  100  feet.  Its  fruit  hangs  in  clusters  up- 
wards of  a  yard  in  length.  The  natives  procure  the  sap  by  cutting 
short  one  of  the  shoots  that  is  about  to  flower  and  carry  fruit,  and 
hanging  under  the  cut  part  of  a  calabash  or  other  vessel,  into  which 
the  fluid  distils ;  in  a  large  plantation  such  an  apparatus  is  seen 
connected  with  each  palm-tree ;  the  sap  is  removed  every  morning, 
and  it  is  enough  to  reduce  it  by  evaporation  to  obtain  the  sugar, 
which  diflfers^  in  no  respect  from  the  finest  sugar  of  the  cane ;  in  the 
unrefined  state  it  is  known  over  the  whole  of  the  East  under  the 
name  of  jaggery,*  and  is  then  a  kind  of  moist  and  sticky  muscovado 
sugar.  The  sap  of  the  palm-tree  obtained  in  the  way  above  indica- 
ted, is  often  turned  into  a  vinous  liquor,  which  is  much  prized  in 
many  places.  The  pith  of  the  tree  yields  sago.  The  palm-trees 
cultivated  in  India  consequently  yinld  three  most  useful  products — 
sugar,  oil,  and  the  farinaceous  article  of  diet  called  sago.  In  rear- 
ing the  cocoa-nut  palm,  those  nuts  are  selected  for  seed  which  fall 
naturally,  and  they  are  dried  in  their  husk.  The  ground  which  is 
to  be  sown  is  dug  to  a  depth  of  eighteen  or  twenty  inches,  and  it  is 
left  *o  settle  for  three  or  four  days.  Some  portion  of  the  surface  is 
then  taken  away,  and  the  fresh  soil  is  covered,  to  the  depth  of  about 
six  inches,  with  sand.  The  nuts  are  then  placed  upon  the  ground 
80  prepared,  and  covered  over  with  a  little  sand  and  a  light  stratum 
of  vegetable  mould  ;  they  are  then  watered  for  three  days  consecu- 
tively. In  the  course  of  three  months  the  young  palms  are  fit  to  be 
transplanted,  and  they  are  set  at  the  distance  of  about  twenty  feet 
every  way  from  one  another.     For  their  reception  in  the  permanent 

♦  This  is  the  generic  name  for  sugar,  and  is  obviously  cither  the  Latin  word  sac- 
charum,  or  from  the  same  root  as  the  Lntin  word.  The  cocoa-nut  tree  treated  in  llie 
tame  way  as  the  cleophora  yields  abundance  of  sugar,  which  is  also  known  under  the 
Baoie  of  j-dggery. — Eiio.  Ed. 


GRAPE-SUG^R,    OR    GLUCOSE..  127 

plantation,  holes  are  dn^  of  about  two  feet  in  depth,  in  which  a 
layer  of  sand,  about  six  inches  in  depth,  is  put,  upon  which  the  young 
plants,  still  adherif)>T  to  the  fruit,  are  placed  ;  the  hole  is  then  filled 
with  sand,  and  the  surface  is  covered  with  a  little  earth.  The  young 
trees  require  watering  every  day  during  about  three  years.'  The 
palm  begins  to  be  productive  at  the  age  of  seven  or  eight  years,  and 
it  continues  to  yield  fruit,  or  sap  for  the  manufacture  of  sugar,  during 
a  very  considerable  period,  without  causing  any  further  cost  l')r  cul- 
tivation.* The  sap  of  the  greater  number  of  the  palms  appears  to 
be  rich  in  saccharine  matter  ;  it  is  obvious,  indeed,  that  every  sap 
that  is  capable  of  supplying  a  vinous  liquor  by  fermentation,  may 
also  furnish  sugar ;  and  if  the  palms  have  not  generally  been  grown 
with  a  view  to  this  product,  it  is  because  the  fruit  must  then  be 
given  up,  and,  both  in  India  and  South  America,  the  produce  in  the 
shape  of  oil  from  the  nuts  of  the  palm,  is  almost  always  more  valu- 
able than  that  which  can  be  had  in  the  shape  of  sugar.f 

GRAPE    SUGAR. 

We  have  already  said  that  starch  acted  upon  by  acids,  and  by 
malted  barley,  is  changed  into  a  saccharine  fermentable  substance, 
which,  both  in  regard  to  flavor  and  physical  properties,  differs  in 
many  respects  from  the  sugar  which  we  have  hitherto  been  engaged 
in  studying.  As  this  substance  exists  naturally  in  the  grape,  it  has 
been  called  grape  sugar,  a  name  for  which  the  generic  term  glucose 
has  been  lately  substituted  in  France,  this  term  being  used  to  include 
all  the  sugars  that  are  analogous  to  grape  sugar.  Grape  sugar  oc- 
curs in  the  form  of  small  white  and  very  soft  crystals,  grouped  in 
tubercular  masses;  it  softens  at  60°,  (140°  Fahr.,)  and  becomes 
quite  sirupy  at  90°,  (194°  Fahr.)  Alcohol  free  from  water  dissolves 
none  of  it ;  but  diluted  alcohol  takes  up  a  considerable  quantity. 

In  the  grape  this  sugar  is  associated  w^ith  cream  of  tartar,  tartrate 
of  lime,  and  several  other  saline  matters.  It  is  easily  extracted 
from  the  fruit ;  but  the  grape  sugar  of  commerce  is  now  universally 
prepared  from  starch  ;  large  quantities,  indeed,  are  manufactured  on 
the  continent  for  the  preparation  of  spirit,  and  for  the  amelioration 
of  wine,  beer,  cider,  &c.,  in  short,  to  supply  sugar  wherever  it  is 
defective  in  the  natural  or  artificial  musts  that  are  subjected  to  fer- 
mentation. In  England  considerable  quantities  are  also  manufac- 
tured ;  but  here  the  law  does  not  allow  it  to  be  used  in  the  same  ad- 
vantageous direction  as  in  France  and  Germany  ;  all  that  is  made  is 
employed  for  mixing  with  adulterating  cane  sugar,  which  is  an  arti- 
cle of  higher  price. 

The  sugar  that  is  made  from  starch,  and  that  is  obtained  from  the 
grape  are  identical  in  composition,  as  is  that  also  which  is  found  in 
the  urine  of  persons  laboring  under  diabetes. 

*  Buchanan.    A  Journey  from  Madras,  &c.,  vol.  i.  p.  155. 

t  In  British  India  the  cocoa-nut  palm  is  beginning  to  be  extensively  cultivated  as  a 
means  of  producing  sugar.  A  considerable  portion  of  the  East  India  sugar  now  brought 
to  market,  is  manufactured  from  the  palm-tree.  It  is  not  improbable,  indeed,  that  the 
paLm  of  one  spcies  or  another  will  one  day  supersede  the  sugar-cane  and  the  beetoa 
tlw  source  of  all  Uxe  sngar  consumed  in  Eorope.— Eico.  Ei>. 


138  MAMNA. 

Grape  Sitp&r  Sugar  ( f  Starch.  Diabetic  Surar 

(Saussufe.)  (Gutrin.)  (Pelig-oi.J 

Carbon 36.7  36.1  36.4 

Hydrogen 6.8  7.6  7.0 

Ozygen .56.5  56.9  56.6 

100.0  100.0  100.0 

Like  cane  su^r,  grape  sugar  in  combining  with  certain  bases 
ibandons  a  portion  of  its  constitutional  water.  In  the  state  in  which 
it  is  combined  with  the  oxide  of  lead  it  contains — 

Carbon 43.3 

Hydrogen 6.3 

Oxygen 50.4 

iooio 

From  these  analyses  it  appears  that  crystallized  grape  sugar  con- 
sists of — 

Anhydrous  glucose 100 

Water 19 

On  comparing  the  two  kinds  of  sugar  in  the  crystallized  state,  it 
becomes  evident  that  glucose  or  grape  sugar  does  not  differ  from 
cane  sugar,  except  in  containing  a  larger  quantity  of  water.  In  fact 
the  composition  of  grape  sugar  may  be  represented  in  this  way  : 

Carbon 42.2  i 

Hydrogen 6.2  >    100  of  cane  sugar. 

Oxygen 51.6) 

115.8  of  grape  sugar. 

The  cane,  the  beet,  the  palm,  the  maple,  the  vine,  and  starch, 
turned  into  glucose,  are  the  sources  from  whence  all  the  sugar  of 
commerce  is  obtained  at  the  present  day,  although  attempts  more  or 
less  successful  have  also  been  made  to  extract  sugar  from  the  pine- 
apple, from  the  chestnut,  from  the  sweet  orange,  and  from  the  stem 
of  the  maize  or  Indian  corn.  It  appears  that  before  the  conquest 
the  Mexicans  prepared  a  sirup  from  the  stem  of  the  Indian  corn, 
which  was  sold  in  the  market-places.  Pallas  could  not  obtain  more 
than  about  3  per  cent,  of  crystallized  sugar  from  maize,  but  in  "xn 
experiment  which  I  made  in  South  America  along  with  M.  RouL.i, 
the  quantity  of  raw  sugar  obtained  from  this  plant  was  6  per  cent. 

SACCHARINE    PRINCIPLES    NOT    FERMENTABLE. 

Manna ;  mannite.  This  saccharine  principle  is  met  with  in  dif- 
ferent plants  ;  it  has  been  found  in  the  expressed  juice  of  onions, 
and  in  that  of  asparagus,  in  the  alburnum  of  several  species  of  pine- 
trees,  and  in  different  mushrooms.  Manna,  which  is  an  exudation 
from  the  fraxinus  omus  and  larch,  contains  nearly  ^ths  of  its  weight 
of  mannite,  and  it  is  therefore  from  this  substance  that  mannite  is 
usually  obtained,  although  it  can  also  be  had  from  the  juice  of  the 
beet  and  the  onion  ;  but  then  it  is  necessary  to  destroy  the  cane  or 
grape  sugar  which  they  contain  by  pre^  jous  vinous  fermentation, 


PECTINE.  lt?9 

and  M.  Pelouze  has  even  maintained  that  the  mannite  thus  prepared 
is  a  product  of  fermentation.* 

Mainite  crystallizes  in  very  white  semi-transparent  needles  ;  it 
has  a  slightly  sweet  taste,  and  is  soluble  in  water.  According  to 
Tiiebig  and  Opperman  it  contains  : 

Carbon 39.6 

Hydrogen 7.7 

Oxygen ..52.7 

100.0 

Liquorice,  This  substance,  which  is  obtained  from  the  root  of 
the  Glycirrhiza  glabra,  is  too  well  known  to  require  particular  con- 
sideration ;  it  is  soluble  both  in  water  and  in  alcohol. 

GUM. 

Gum  is  a  substance  very  extensively  diffused  in  the  vegetable 
kingdom ;  there  is,  perhaps,  no  plant  which  does  not  contain  some. 
Gum  is  divided  into  two  kinds  ;  gum,  properly  so  called,  the  type 
of  which  we  have  in  gum-arabic,  and  vegetable  mucilage,  such  as 
we  meet  in  gum-tragacanth. 

Gum  in  dissolving  in  water  produces  a  thick  and  adhesive  fluid. 
It  is  insoluble  in  alcohol.  Some  plants  contain  such  a  quantity  that 
upon  infusion  they  seem  to  give,  as  it  were,  nothing  else  :  such  are 
the  althea,  the  malva  officinalis,  &c. 

Gum  does  not  crystallize,  it  is  met  with  in  concrete  masses  which 
result  from  the  solidification  of  the  drops  which  flow  spontaneously 
from  the  trees  that  yield  it :  by  long  boiling  with  dilute  sulphuric 
acid  it  is  changed  into  glucose.  Nitric  acid  alters  it,  and  several 
new  products  are  the  result,  among  the  number  of  which  is  mucic 
acid.  Gum-arabic,  according  to  the  analysis  of  M.  Gay-Lussac  and 
Thenard,  consists  of : 

Carbon  42.3 

Hydrogen   6-9 

Oxygen -  50.8 

100.0 

To  obtain  vegetable  mucilage,  a  quantity  of  linseed  is  treated  with 
water  and  expressed.  It  is  also  obtained  by  steeping  gum  traga- 
canth  in  about  1000  parts  of  water  and  pouring  oflf  the  solution  which 
covers  the  mucilaginous  mass.  The  mucilage  then  forms  a  jelly 
more  or  less  consistent,  which  diluted  with  a  large  quantity  of  water 
forms  a  ropy  viscid  fluid.  Dried  again,  this  mucilage  becomes  hard 
and  translucid  ;  in  water  it  regains  its  former  state. f 

VEGETABLE  JELLY PECTINE  AND  PECTIC  ACID. 

It  is  well  known  that  the  juice  of  all  fruits  contains  a  gelatinous 
substance  to  which  many  of  them  owe  the  property  of  forming  jellies. 

*  Annales  dc  Chimie,  vol.  xlvii.  p.  419,  2d  series.— The  refuse  wash  of  the  distiller, 
appreciated  by  the  taste,  appears  to  contain  a  consideraMe  quantity  « f  saccharine 
matter,  which  is  probably  mannite.— Eng.  Ed. 

t  Berzelius,  Chemistry,  vol.  v. 


130  PECTINE,  PE.nC  ACID. 

This  matter  may  be  obtained  by  means  of  alcohol.  If  into  a  quantity 
of  currant  juice  lately''  expressed,  a  portion  of  alcohol  be  poured,  a 
gelatinous  precipitate  is  formed  after  a  certain  time  ;  this  jelly,  sub- 
jected to  graduated  pressure  and  washed  with  diluted  alcohol,  gives 
the  gelatinous  principle  in  a  state  of.tolerable  purity  :  this  is  pectine, 
discovered  by  M.  Braconnot. 

Pectine  dried  is  in  membranous  semi-transparent  pieces  resem- 
bling isinglass.  Thrown  into  about  one  hundred  times  its  weight  ot 
water  it  swells  considerably  and  at  length  dissolves  completely, 
giving  rise  to  a  stiff  jelly.  By  increasing  the  quantity  of  water,  a 
mucilaginous  solution,  having  a  slightly  milky  aspect,  is  obtained. 

Pure  pectine  is  quite  insipid  ;  it  does  not  affect  the  color  of  litmus, 
the  weaker  acids  have  no  effect  upon  it ;  a  slight  excess  of  potash  or 
of  soda  does  not  change  it  obviously,  and  nevertheless  pectine  is 
singularly  modified  under  the  influence  of  these  alkalies,  being  chang- 
ed into  a  particular  body,  having  acid  reaction  ;  for  on  saturating 
the  alkali  employed,  it  immediately  coagulates  into  a  transparent 
gelatinous  mass — pectic  acid.  As  pectine  acted  upon  by  the  fixed 
alkalies  undergoes  so  remarkable  a  change,  we  may  be  allowed  to 
conclude,  w-ith  M.  Braconnot,  that  the  pectic  acid  which  is  found 
ready  formed  in  plants,  has  a  similar  origin  ;  a  view  moreover  which 
tends  to  confirm  that  formerly  announced  by  A^'auquelin,  when  he 
ascribed  the  development  of  the  acids  of  vegetables  to  the  presence 
of  alkalies.* 

Gelatinous  pectic  acid  immediately  becomes  defluent  upon  the 
addition  of  a  few  drops  of  solution  of  ammonia.  By  evaporating 
this  solution  in  a  porcelain  dish  we  obtain  an  acid  pectate  of  am- 
monia, which  swells  in  distilled  water,  dissolves  in  it,  and  thickens 
a  large  quantity  of  the  fluid.  As  ammonia  has  no  reaction  upon 
pectine,  M.  Braconnot  has  taken  advantage  of  this  negative  property 
to  determine  if  pectic  acid  exists  or  not,  ready  formed,  in  certain 
plants.  Thus  in  treating  carrots  with  cold  water,  rendered  slightly 
ammoniacal,  a  liquid  is  obtained,  from  which  an  acid  immediately 
throws  down  a  precipitate  of  pectic  acid.f  Pectine  and  pectic  acid, 
therefore,  may  exist  together  in  vegetables,  and  M.  Jacquelain  has 
proved  that  the  acid  there  is  often  in  a  state  of  combination  as  an 
alkaline  or  earthy  pectate.  Tt  is  to  these  pectates  that  M.  Payen 
ascribes  the  origin  of  the  carbonates  of  the  same  bases,  which  are 
met  with  in  the  ashes  of  plants,  the  organic  acid  having  of  course 
beon  destroyed  by  the  combustion. J 

M.  Braconnot  has  described  an  easy  process  for  obtaining  pectic 
acid  in  large  quantity  from  carrots.^ 

M.  Fremy  has  published  analyses  of  pectine  and  pectic  acid,  which 
present  this  remarkable  peculiarity,  that  the  cne  has  exactly  the 
fiame  elementary  composition  as  the  other. 

*  Braconnot,  Annals  of  Chemistry,  vol.  xlvii.  p.  274,  Si  icries 
t  Braconnot,  op.  cit.  vol.  xxx.  p.  99. 

i  Payen,  Proceedings  of  the  Academy  of  Sciences,  vol.  XV.p.90T 
i  Op.  cit.  VOL  XXX.  p.  97.  "^ 


I 


VEGETABLE   ACIDS.  181 

Pectine.  reetl9«ci4. 

Carbon 42.9  42.8 

Hydrogen 5.1  5.2 

Oxygen 52.0  52.0 

100.0  100.0 

I  have  thought  it  right  to  speak  at  some  length  of  these  two  prin- 
ciples, as  they  appear  to  play  an  important  part  ii  the  phenomena  of 
vegetable  life.  A  careful  study  of  pectine  and  pectic  acid  will  very 
probaMy  aid  in  throwing  light  upon  the  metamorphoses  which  organic 
substances  undergo  in  the  act  of  vegetation.  Pectic  acid  has  been 
found  in  every  plant  in  which  it  has  been  sought  for  ;  M.  Braconnot 
discovered  it  in  the  turnip,  carrot,  beet,  peony,  in  all  bulbs,  in  the 
stalks  and  leaves  of  herbaceous  plants,  in  the  wood  and  bark  of  all  the 
trees  examined,  in  all  kinds  of  fruit,  apples,  pears,  plums,  cucumbers, 
&c,  M.  Braconnot  is  even  very  much  inclined  to  think  that  pectic 
acid  may  constitute  the  essential  principle  in  the  cambium  or  organ- 
izable  matter  of  Grew  and  Duhamel.* 

OP   VEGETABLE    ACIDS. 

w 

In  the  series  of  bodies  which  we  have  now  considered,  one  only, 
sugar,  possesses  the  property  of  crystallizing.  All  the  others  are 
amorphous,  and  their  globular  disposition  and  gelatinous  qualities 
have  led  to  the  presuniption  that  they  form  in  some  sort  the  line  of 
demarcation  between  things  without  and  things  endowed  with  life. 
It  was  also  imagined  that  these  amorphous  matters,  that  these  pro- 
ducts of  the  vegetable  organization,  almost  organized  themselves, 
would  alone  suffice  for  the  nourishment  of  animals.  This  idea, 
however,  is  not  well  founded  ;  for  if  it  be  true  that  albumen,  caseine, 
legumine,  starch,  and  gum,  are  powerful  elements  of  nutrition,  it  is 
equally  so  that  sugar  may  perform  an  important  part  in  this  process, 
by  acting  in  the  same  manner  as  starch,  the  oils,  and  other  principles 
of  ternary  composition,  in  becoming  like  them  a  useful,  often  an  in- 
dispensable auxiliary  of  azotized  alimentary  matters. 

This  disposition  to  consider  the  amorphous  state  of  the  more  im- 
portant immediate  principles  of  vegetables  as  a  special  and  distinctive 
character,  cannot  be  maintained  beside  the  recent  observations  of 
Mitscherlich.  This  illustrious  chemist  has  found,  that  if  the  mineral 
precipitates  which  are  deposited  in  liquids,  are  in  many  cases  form- 
ed of  crystals  more  or  less  regular,  they  are  also  sometimes  compos- 
ed of  small  spheres  or  aggregated  masses,  the  particles  of  which  do 
not  unite  in  a  regular  way  as  crystals,  but  remain  separated  by  a 
thin  layer  of  fluid.  Examined  under  the  microscope  these  masses 
present  themselves  under  the  form  of  flocks  and  of  shreds,  having  a 
granular  or  gelatinous  appearance,  and  which  xcmain  soft  and  flexi- 
ble like  fresh  vegetable  or  animal  substances,  so  long  as  they  are 
kept  under  water ;  it  is  only  in  drying  that  they  become  pulverulent 
or  acquire  the  vitreous  aspect. f 

*  Braconnot,  op.  cit.  vol.  xxviii.  p.  171. 
1  Berzelius,  Ann.  Report,  ISil,  p.  20. 


132  VEGETABLE    ACIDS. 

The  substances,  the  chemical  constitution  of  which  we  have  still 
te  examine,  may  in  general  be  obtained  in  the  crystallized  state ; 
their  individuality  seems  more  decided  ;  they  are  more  stable,  better 
characterized,  and  their  specific  properties  often  assimilate  them  to 
inorganic  bodies.  Such,  for  example,  are  the  acids  formed  in  the 
course  of  vegetable  existence. 

Vegetable  acids  present  all  the  general  characters  of  mineral 
acids,  while  they  participate  in  the  properties  inherent  in  organic 
substances.  Thus  they  form  salts  by  uniting  with  bases  ;  with 
potash,  soda,  ammonia,  they  form  salts  soluble  in  water ;  the  other 
bases  produce  compounds  that  are  soluble  or  insoluble,  according  to 
the  nature  of  the  acid.  These  acids,  free  or  uncombined,  are  very 
frequently  met  with  in  fruit,  sometimes  in  the  leaves,  more  rarely 
in  the  seeds  and  roots  ;  but  in  combination  with  bases  they  are  met 
with  in  almost  all  parts  of  plants.  Already  very  numerous,  they  are 
increasing  rapidly  with  the  progress  of  discovery ;  with  the  excep- 
tion of  a  very  few  employed  in  the  arts,  their  study  forms  a  subject 
of  no  great  interest.  I  shall  therefore  confine  myself  to  a  few  of  the 
most  extensively  distributed  of  these  acids. 

Oxalic  acid.  This  acid  exists  free  in  the  hairs  of  the  cicer  or 
chick-pea,  and  united  with  potash  constituting  an  acid  salt,  the  bin- 
oxolate  of  potash  in  the  wood  sorrel  and  the  common  or  garden  sor- 
rel. It  is  from  the  former  of  these  plants  that  the  salt  called  salt 
of  lemons,  but  which  is,  in  fact,  the  binoxolate  of  potash,  is  still  ex- 
tracted in  some  countries.  The  juiceof  the  wood  sorrel  is  expressed 
and  yields  about  0.003  of  its  weight  of  the  salt,  from  which,  by  or- 
dinary chemical  manipulation,  the  oxalic  acid  is  readily  obtained. 
At  the  present  time  this  acid  is  prepared  artificially  by  the  action  of 
nitric  acid  upon  starch  ;  it  is  a  powerful  acid,  and  its  affinity  for  lime 
is  such  that  it  takes  this  base  even  from  its  union  with  sulphuric 
acid. 

Tartaric  acid  is  met  with  above  all  in  the  grape  in  the  state  of 
bitartrate  of  potash,  a  salt  which  is  deposited  upon  the  sides  of  the 
casks  in  which  the  wine  is  kept.  After  having  been  properly  puri- 
fied, it  is  known  in  commerce  under  the  name  of  cream  of  tartar, 
from  which  the  tartaric  acid  can  readily  be  obtained.  Another  par- 
ticular acid,  the  racemic  acid,  the  composition  of  which  is  identical 
with  that  of  the  tartaric  acid,  has  been  discovered  in  the  tartar  of 
the  wines  grown  on  the  Upper  Rhine. 

Citric  acid.  This  acid  is  found  in  the  juice  of  many  plants,  and 
abundantly  in  the  juice  of  lemons,  oranges,  currants,  &c.  It  is  from 
the  lemon  and  the  lime  that  the  citric  acid  employed  in  the  arts  19 
generally  obtained. 

Tannic  acid.  A  certain  substance  which  is  met  with  in  the  bark 
of  particular  trees,  and  which  has  the  valuable  property  of  renderings 
the  hides  of  animals  with  which  it  is  combined  insusceptible  of  pu- 
trefaction, is  familiarly  known  under  the  name  of  tannin.  The  art 
of  the  tanner  is  founded  upon  this  property  of  tannin.  A  solution 
cf  gelatine  being  poured  into  an  infusion  of  tannic  acid,  an  insoluble 
precipitate,  torm.ed  by  the  uiiiun  ot  the  acid  with  the  animal  matter, 


VEGETABLE    ALKALIES. 


133 


IS  immediately  produced.  By  macerating  a  piece  of  raw  hide  in  a 
solution  of  tannin,  the  same  combination  takes  place  even  into  the 
very  interior  of  the  tissue  ;  the  whole  of  the  tannin  quits  the  solu- 
tion by  degrees  to  combine  with  the  gelatine  of  the  skin. 

It  is  not  in  the  bark  only  that  tannin  is  encountered,  it  has  been 
found  in  different  organs  of  plants.  Sir  Humphrey  Davy  has  stated 
these  quantities  of  tannin  as  constituents  of  100  parts  of  the  follow^ 
ing  substances  : 


Nutgalls   . 

27.4 

Oak  bark 

,         , 

6.3 

Chestnut  bark 

. 

4.3 

Elm  bark 

. 

2.7 

Willow  bark     . 

2.2 

Inner  white  bark  of  an 

aged  oak 

15.0 

The  same  of  young  oaks" 

16.0 

The  same  of  the  Indian 

chestnut 

15.2 

The  inner  colored  bark  of  the  oak 

4.0 

Sicilian  sumac 

16.2 

Malaga  sumac 

10.4 

Souchong  tea 

10.0 

Green  tea 

8.5 

Bombay  catechu 

54.3 

Bengal  catechu 

48.1 

Gallic  acid.  This  acid  is  found  united  with  tannin  in  the  greater 
number  of  barks,  or  along  with  the  astringent  principles  of  plants. 
Gallic  acid  appears  to  be  the  product  of  a  kind  of  fermentation  un- 
dergone by  tannin,  as  the  process  by  which  it  is  prepared  seems  to 
indicate,  and  which  consists  essentially  in  exposing  for  about  a 
month  a  quantity  of  nutgalls  reduced  to  powder  and  kept  constantly 
moistened.  The  solution  of  gallic  acid  does  not  precipitate  gela- 
tine. 

I  have  added  in  a  table  the  composition  of  the  principal  vegetable 
acids.  I  shall  speak  of  the  composition  of  fat  acids  when  I  come  to 
treat  of  fatty  substances. 

The  different  vegetable  acids  do  not  vary  essentially  in  composi- 
tion, save  in  a  single  instance.  With  one  exception  they  consist  of 
definite  proportions  of  carbon,  hydrogen,  and  oxygen.  The  excep- 
tion alluded  to  is  the  hydrocyanic  acid,  which  contains  no  oxygen, 
but  a  large  quantity,  nearly  52  per  cent.,  of  azote. 

OF  THE  VEGETABLE  ALKALIES. 

The  alkaline  bases  which  are  formed  in  the  course  of  vegetation, 
always  contain  a  certain  proportion  of  azote.  Their  general  prop- 
erties are  those  of  alkalies ;  their  watery  or  alcoholic  solutions  re- 
store the  blue  color  of  the  reddenea  tincture  of  turnsole,  and  they 
constitute  salts  by  combining  with  acids.  In  their  manner  of  be- 
having they  bear  a  certain  analogy  to  ammonia.  Like  ammonia, 
the  organic  alkalies  combine  with  the  hydrates  of  the  oxacids,  and 
when  they  are  deprived  of  their  water  of  crystallization,  they  fix  the 
hydracids  without  losing  weight. 

12 


134  FATTY  SUBSTANCES. 

The  discovery  of  the  vegetable  bases  is  due  to  Sertuerner,  wh(.», 
in  1804,  indicated  the  existence  of  morphine  in  opium.  The  ma- 
jority of  the  vegetable  alkalies  are  insoluble,  or  little  soluble  in 
water  ;  all  are  soluble  in  alcohol ;  some  of  them  are  sutRciently 
volatile  to  be  susceptible  of  distillation. 

In  elementary  composition  they  are  all  very  much  alike,  consist- 
ing of  various,  but,  in  each  instance,  definite  proportions  of  carbon, 
hydrogen,  oxygen,  and  azote,  the  carbon  varying  from  about  50  to 
75,  the  hydrogen  from  6  to  12,  the  oxygen  from  8  or  9  to  27  and 
even  37,  and  the  azote  from  1.6  to  12,  28,  and  even  35  per  cent. 

OF  FATTY  SUBSTANCES. 

Under  this  title  I  comprise  all  the  oily  substances,  liquid  or  solid, 
and  those  that  are  analogous  to  wax,  which  are  found  disseminated 
in  different  organs  of  plants.  A  character  common  to  almost  all 
fatty  substances,  is  insolubility  in  water.  They  dissolve  in  sensible 
quantity  in  alcohol,  and  especially  in  ether.  Fatty  substances  may 
be  divided  into  two  classes  :  one  including  those  which  are  easily 
modified  by  the  action  of  alkalies,  and  which  form  soaps ;  the  other 
not  susceptible  of  this  action,  not  susceptible  of  saponification,  or,  at 
all  events,  that  are  only  attacked  by  alkalies  in  very  particular  cir- 
cumstances. 

When  a  mixture  of  fat  oil  and  a  solution  of  caustic  alkali  are 
heated,  the  oil  is  soon  observed  to  incorporate  with  the  alkaline 
liquid.  After  boiling  for  some  time,  if  the  alkali  is  in  excess,  clots 
or  flocks  appear,  and  in  removing  the  excess  of  liquid  a  white  mass 
is  obtained  which  is  soluble  in  water — the  oil  is  saponified  ;  and  the 
product  of  the  saponification  is  combined  with  a  portion  of  the  alkali 
which  has  been  employed.  If  into  a  hot  solution  of  this  soap  a 
quantity  of  hydrochloric  acid  be  poured,  the  acid  seizes  upon  the  pot- 
ash or  the  soda,  setting  at  liberty  the  fatty  body  which  had  been 
combined  with  the  alkali,  and  which  collects  on  the  liquid.  It  is 
easy  to  discover  that  the  fatty  matter  thus  collected  is  no  longer  the 
same  as  that  which  had  been  originally  employed  ;  for  example,  it  is 
completely  soluble  in  boiling  alcohol,  which,  on  cooling,  deposites 
brilliant  pearly  crystals  of  a  fatty  substance  possessing  acid  proper- 
ties. By  evaporating  the  alcohol  from  which  these  crystals  are 
formed,  an  additiona  quantity  is  obtained,  and,  when  the  alcohol  is 
entirely  dissipated,  another  unctuous  body  is  obtained,  having  also 
acid  properties.  Three  acids  having  distinguishing  characters  are, 
in  fact,  obtained  by  the  action  of  alkalies  upon  fatty  substances  :  the 
stearic,  margaric,  and  oleic  acids.  The  alkalies  consequently  trans- 
form neutral  oily  bodies  into  acid  substances,  as  first  shown  by  the 
admirable  researches  of  M.  Chevreul,  before  whose  time  it  was  al- 
ways assumed  that  soap  was  the  result  f  f  a  direct  union  of  fatty 
matters  with  alkalies.  The  fatty  acids  arc  not  the  only  products  of 
saponification,  there  are  several  others,  particularly  glycerine,  which, 
however,  need  not  occupy  us  particularly  here. 

The  experiments  of  M.  Chevreul  would  lead  us  to  view  all  fatty 


FATTY  SUBSTANCES.  185 

matters  as  combinations  of  glycerine  playing  the  part  of  a  uase  with 
particular  acids  ;  these  combinations,  analogous  to  salts  if  their  con- 
stitution be  merely  considered,  are  generally  mixed  together  us  oils 
and  fats  ;  thus  the  union  of  stearic  acid  and  glycerine  forms  stearine, 
which  is  fusible  at  the  temperature  of  about  62°  cent,  (144°  Fahr.) 
Stearic  acid  melts  at  72°  cent.,  (162°  Fahr.,)  oleine  remains  fluid  at 
4°  cent.,  (24°  Fahr.,)  and  oleic  acid  is  liquid.  An  oil  is,  therefore, 
by  so  much  the  more  consistent  as  a  larger  quantity  of  solid  fatty 
acid  enters  into  its  composition,  and  it  is,  on  the  contrary,  by  so 
much  the  softer  and  more  liquid  as  this  acid  is  itself  more  fluid.  The 
wax  of  the  Myrica  cerifera,  for  example,  is  sufficiently  hard  to  be 
reduced  to  powder,  and  is  almost  entirely  formed  of  stearine.  In 
the  fluid  vegetable  oils  oleine  always  predominates.  It  is  easy  to 
separate  these  different  fatty  compounds  from  one  another. 

Besides  the  solid  and  litjuid  acids  which  are  obtained  from  fatty 
substances,  there  are  others  known  which  are  volatile. 

Fatty  bodies  absorb  oxygen  from  the  air.  This  absorption  is  at 
first  extremely  slow,  scarcely  appreciable ;  but  once  begun,  it  goes 
on  with  great  rapidity  ;  so  rapidly,  indeed,  that  if  a  large  surface  be 
exposed  to  the  air,  if,  for  example,  a  quantity  of  rags  or  tow  be  im- 
pregnated with  oil,  the  mass  may  take  fire.  The  consequence  of 
this  oxidation  is  always  a  thickening  of  oil,  and  there  are  some  which 
become  completely  solid  in  its  course  ;  these  are  designated  by  the 
title  of  drying  oils,  and  are  in  particular  request  for  the  manufacture 
of  varnishes.  Nut  oil  which  has  remained  long  exposed  to  the  air 
acquires  the  consistence  of  jelly,  and  its  unctuous  properties  have  sc 
entirely  disappeared  that  it  no  longer  stains  paper. 

The  alteration  which  fatty  substances  undergo  in  contact  with  air 
and  moisture  is  still  more  remarkable.  The  oils  which  are  inodorous 
and  without  taste  soon  acquire  under  these  circumstances  a  strong 
smell  and  a  disagreeable  flavor.  Fleshy  fruits  which  contain  a  large 
quantity  of  oil,  such  as  the  olive  and  the  oleaginous  seeds,  when 
moistened  suffer  true  fermentation,  the  result  of  which  is  the  sepa- 
ration of  the  fatty  acids  from  the  glycerine. 

Oils  subjected  to  the  action  of  a  high  temperature  are  alsb  greatly 
modified.  The  glycerine  which  they  contain  is  decomposed,  and 
gives  rise  to  various  pyrogenous  products  :  stearic  acid  is  changed 
into  margaric  acid,  and  oleic  acid  into  sebacic  acid,  a  crystallizable 
volatile  acid  which  is  soluble  in  hot  water. 

The  fatty  substances  of  plants  are  principally  accumulated  in  the 
fruit,  and  particularly  in  the  seed.  In  the  herbaceous  parts  they  are 
less  abundant,  less  perfectly  elaborated.  Oils  appear  to  be  included 
in  the  vegetable  tissue  under  the  form  of  globules,  or  minute  drops. 
In  such  an  oily  seed  as  the  common  almond,  when  it  is  growing,  we 
perceive  that  the  cellular  tissue  is  in  the  first  instance  full  of  a  col- 
orless and  transparent  fluid  ;  but  as  the  seed  advances,  each  cell  is 
seen  to  become  filled  with  numbers  of  little  oil  globules  which  in- 
crease continually  in  size  and  number  until  the  kernel  is  ripe  ;  there 
is  at  the  same  time  a  quantity  of  azotized  matter  deposited  in  the 
midst  of  the  liquid,  which  disturbs  its  transparency  ;  it  is  this  depos- 


136  FATTY    SUBSTANCES. 

ite  which  thickens  the  walls  of  the  cells.*  The  capillary  force 
which  retains  fatty  principles  combined  with  the  tissue  of  certain 
seeds  must  be  very  considerable,  for  havings  boiled  some  rape-seed, 
wiiich  contained  50  per  cent,  of  oil,  in  water,  there  was  not  a  trace 
of  oily  matter  perceptible  upon  the  surface  of  the  liquid.  Butter 
appears  to  be  kept  diffused  in  milk  by  something  of  a  similar  force, 
for  milk  when  boiled  yields  but  a  very  small  quantity  of  this  sub- 
stance M.  Dumas  and  I  maintain  that  the  oil  of  seeds  is  intended 
for  the  production  of  heat  by  undergoing  combustion  at  the  period 
of  germination  ;  a  series  of  experiments  performed  in  my  laboratory 
by  M.  Letellier  supports  this  opinion. 

Having  ascertained  by  a  preliminary  trial  the  quantity  of  oily 
substance  contained  in  a  certain  weight  of  seed,  some  of  the  same 
kind  was  put  to  germinate,  and  the  quantity  of  oil  which  it  contained 
was  tested  at  two  periods  of  the  germination  ;  it  was  found  that  in 
the  course  of  this  process  a  considerable  proportion  of  the  fatty  sub- 
stance had  disappeared  ;  one  gramme  or  15.438  grains  of  rape-seed 
before  germination  contained  0.50  of  oil ;  after  the  first  period  of 
germination,  namely,  when  the  cotyledons  had  begun  to  turn  green, 
the  quantity  of  oil  was  found  reduced  to  0.43,  and  at  the  end  of  the 
second  period,  when  the  cotyledons  had  become  quite  green  and  the 
radicles  were  from  3.9  to  4.6  inches  long,  the  oil  was  reduced  to  0.28. 

It  would  be  extremely  interesting  to  ascertain  the  extreme  loss 
which  the  oily  principles  of  seeds  sustained  in  the  course  of  the 
commencement  of  vegetation,  and  to  follow  the  return  of  the  same 
principles  in  proportion  as  the  plant  advanced  towards  maturity. 
M.  Letellier  is  going  on  with  these  experiments. 

The  numberless  uses  to  which  oil  is  put,  make  its  manufacture  an 
object  of  the  highest  importance.  Vegetable  oils  are  generally  ob- 
tained from  olives,  from  oleaginous  seeds,  and  from  the  nut  of  cer- 
tain palms.  Oil  is  separated  by  pressure  ;  it  may  often  be  extracted 
from  the  seed  in  the  natural  state,  in  which  case  the  produce  is  of 
fine  quality,  but  seldom  abundant.  The  castor-oil  bean,  for  example, 
yields  its  oil  under  the  simple  action  of  the  press.  In  America, 
however,  to  obtain  this  oil,  the  seeds  are  first  roasted  slightly,  and 
being  bruised  they  are  then  boiled  in  water ;  the  oil  readily  sepa- 
rates from  the  roasted  seed.  A  similar  process  is  sometimes  follow- 
ed in  procuring  cacao  butter. 

In  the  extraction  of  oil  from  the  common  oleaginous  seeds,  they 
are  first  ground  or  bruised  in  a  proper  apparatus  ;  the  paste  or  pow- 
der which  they  now  form  is  generally  heated,  and  being  put  into 
woollen  sacks,  and  these  enclosed  in  hair  bags,  they  are  subjected  to 
the  operation  of  the  press ;  after  one  pressure,  the  magma  which 
remains  in  the  bags  is  crushed  anew,  heated,  and  pressed  again. 
The  oil  obtained  by  the  second  pressing  is  never  so  pure  as  that 
procured  by  the  first. 

The  oil-cake  is  taken  out  of  the  bags,  completely  dry  in  appear- 
BOe»  but  it  still  contains  a  large  proportion  of  oil — iron  8  to  15  per 

*  Domas,  Chemistrj',  vol.  v. 


OIL. 


137 


cent,  of  its  weight.  It  is  used  in  fattening  cattle  and  as  manure 
Oil,  when  newly  expressed,  is  always  turbid  and  very  mucilaginous; 
it  becomes  clear  by  standing ;  but  it  always  retains  certain  8ub« 
stances  which  lessen  its  quality,  particularly  when  it  is  intended 
for  burning  in  lamps. 

Greater  obstacles  are  encountered  in  extracting  the  &i\  from  some 
of  the  pulpy  fruits  than  from  seeds.  In  extracting  olive-oil,  the 
olives  are  crushed  under  millstones ;  and  the  paste  which  results  be- 
ing put  into  flat  baskets  of  wicker-work,  is  subjected  to  the  press. 
The  first  pressing  yields  virgin  oil,  which  is  used  for  the  table. 
Having  removed  the  baskets  from  the  press,  their  contents  are  mix- 
ed with  a  little  boiling  water,  replaced,  and  pressed  again,  by  which 
a  new  quantity  of  oil  is  obtained.  But  the  pulp  is  not  yet  exhausted  , 
by  special  treatment  it  still  yields  a  quantity  of  oil  of  inferior  quality, 
which  is  employed  in  the  manufacture  of  soap. 

The  fruit  of  the  palm  yields  the  oil  which  it  contains  with  great 
readiness.  I  have  extracted  a  butter  of  excellent  quality  and  very 
agreeable  taste  by  simply  boiling  the  nuts  or.  berries  of  the  Palma 
real  in  water.  The  cocoa-nut  yields  two  qualities  of  oil,  according 
to  the  mode  of  extraction.  To  prepare  the  best  kind,  the  fleshy 
part  of  the  fruit  is  grated,  and  the  pulp  being  pressed,  a  milky  fluid 
is  obtained,  which  yields  the  oil  by  boiling.  An  inferior  quality  of 
oil  is  obtained  by  causing  the  cocoa-nuts  to  putrefy  ;  when  the  putre- 
faction has  advanced  to  a  certain  stage,  the  oily  pulp  is  thrown  into 
copper  vessels  and  exposed  to  the  sun,  and  the  oil  which  then  rises 
to  the  surface  is  skimmed  off.  This  oil  is  brown,  and  has  a  strong 
smell ;  it  contains  fatty  acids  which  have  probably  been  set  at  lib- 
erty by  the  putrid  fermentation. 

The  value  of  the  produce  in  oleaginous  seeds  of  a  given  extent 
of  land,  and  the  quantity  of  oil  which  these  seeds  will  yield,  depend, 
as  may  readily  he  conceived,  on  a  variety  of  causes  which  it  is  not  al- 
ways easy  to  appreciate  with  precision  ;  such  as  climate,  the  nature 
of  the  soil,  the  system  of  husbandry  followed,  &c.  The  observations 
of  M.  Gaujac  of  Dagny  on  the  various  plants  usually  cultivated  for 
the  sake  of  their  oleaginous  seeds,  will  however  suffice  to  give  a 
notion  of  their  comparative  productiveness  in  oil  and  cake  : 


Crop. 

Seed  produced 

per  acre  in 

Cwts.    qrs,        lbs. 

Whole  quantity 

of  Oil  obtained 

per  Acre  in  lbs. 

avoird. 

Oil 
obtained 
per  cent. 

Cake 

per  cent. 

WINTER    CROPS. 

Colewort 

19        0        15 

15  1          3 

16  2        18 

15  1        25 

16  2        18 
13        3        19 

17  1        16 
15        3        14 
15        1        25 

10  1        18 
7        3        21 

11  3        17 

875.4 
320.8 
641.6 
595.8 
641.6 
565.4 

545.8 
275.0 
385.0 
560.8 
229.0 
412.5 

40 
18 
33 
33 
33 
33 

27 
15 
22 
46 
25 

54 
73 

62 
62 
62 
61 

72 
80 
69 
52 
70 

Rape 

Swedish  turnip.. 
Curled  colewort. . 
Turnip  cabbage.. 

SPRING    CROPS. 

Gold  of  Pleasure 

Sunflower 

Flax                 .  . • 

White  poppy 

Summer  rape  — 

30 

1        65 

13* 


138  OIL. 

M.  Matthew  de  Dombasle  made  some  comparsiive  experiments  a. 
Roville  on  the  cultivation  of  oleaginous  plants.  The  results  obtain- 
ed by  this  skilful  agriculturist  are  much  less  favorable  than  those  of 
M.  Gaujac.  Instead  of  19  cwt.  and  15  lbs.  of  colewort  seed  yield- 
ing 875.4  lbs.  of  oi;  per  acre,  M.  de  Dombasle  only  obtained  11  cwt. 
2  qrs.  21  \h§.  yielding  392.3  lbs.  of  oil ;  and  the  other  kinds  of  seed 
in  proportion.  But  as  I  have  said  already,  the  fertility  of  the  soil, 
and  the  labor  and  pains  bestowed  upon  it,  may  have  contributed  to 
the  differences  observed,  because  here  the  influence  of  climate  may 
be  overlooked.  There  is  one  circumstance,  however,  which  may 
explain  the  great  differences  in  the  quantity  of  oil  obtained,  which 
is  the  perfection  of  the  press  employed  to  extract  it.  In  a  general 
way  oil-presses  are  so  imperfect  that  they  all  leave  a  quantity  of  oil 
more  or  less  in  the  cake. 

Here  are  two  examples  :  from  2765  lbs.  avoird.  of  fine  colewort 
seed,  gathered  in  1842,  and  weighing  52^  lbs.  per  bushel,  I  obtained  : 

lb«. 

Of  oil 1130.5 

Of  cake 1384.9 

Loss 249.6 

2765.0 

In  Other  terms,  per  cent. : 

Oil 40.81 

Cake 50.12 

Loss 9.07 

iooioo 

but  by  a  careful  analysis  of  the  same  seed  in  the  laboratory,  50  per 
Dent,  of  oil  was  obtained. 

2d.  In  1840  and  1841,  I  made  some  experiments  on  the  cultiva- 
tion of  the  madia  sativa,  intermixed  with  carrots  in  a  fertile  soil, 
well  manured  with  farm  dung.  The  crop  of  the  year  1840  was  ex- 
cellent ;  it  required  one  hundred  and  twenty-seven  days  to  come  to 

maturity. 

ibi. 

Seed,  husks  deducted 2424 

Dried  leaves  employed  as  litter 7700 

Carrots  without  their  leaves 31966 

The  seed  gave  : 

Of  oil 635.8 

Of  cake 17067.6 

100  of  seed  gave  : 

Oil 26.24 

Cake 70.72 

Loss 33.4 

100.00 

These  results  agree  pretty  nearly  with  those  which  have  been 
published  by  ether  agriculturis  s ;  but  the  seed  of  this  madia,  which 
in  the  press  gave  26.24  of  oil  per  cent.,  actually  yielded  41  per  cent, 
by  analysis  in  the  laboratory  ;  this  difference  between  practical  re- 
suits  and  those  of  the  laboratory,  shows  us  how  large  a  quantity  of 
oil  is  generally  left  in  the  ;ake.    When  the  cake  is  used  for  feeding 


OIL.  139 

cattle,  the  loss  is  perhaps  less  to  be  regretted,  inasmuch  as  the  oily 
matter  evidently  assists  in  the  fattening ;  but  when  the  cake  is  used 
as  manure,  \he  oil  which  it  contains  is  almost  entirely  lost. 

It  is  often  ot  importance  to  the  agriculturist  to  ascertain  precisely 
the  quantity  of  fatty  principles  contained  in  oleaginous  seeds.  For 
this  purpose,  it  is  enough  to  bruise  a  given  quantity  of  the  seed  and 
to  digest  it  in  successive  portions  of  sulphuric  ether.  After  a  first 
digestion,  the  seed  is  bruised  or  pul-verized  anew,  and  the  bruising 
is  now  accomplished  without  difficulty.  The  process  may  be  con- 
cluded by  boiling  with  a  mixture  of  equal  parts  of  ether  and  alcohol. 
The  ethereal  solutions  are  decanted  from  the  seed  into  a  porcelain 
dish,  the  weight  of  which  is  known.  The  ether  evaporates  sponta- 
neously and  the  oil  remains,  the  weight  of  which  is  then  taken. 

The  following  sums  may  be  taken  as  a  pretty  accurate  estimate 
of  the  average  quantity  of  oil  yielded  by  the  different  oleaginous 
seeds  :  colewort,  winter  rape,  and  other  species  of  cruciferous  plants, 
from  30  to  36  and  40  per  cent. ;  sunflower  about  15  per  cent.  ;  lin- 
seed from  11  to  22 ;  poppy  from  34  to  63;  hempseed  from  14  to 
26 ;  olives  from  9  to  11 ;  walnuts  40  to  70  ;  brazil  nuts  60 ;  castor- 
oil  beans  62  ;  sweet  almonds  40  to  54 ;  bitter  almonds  28  to  46 ; 
madia  sativa  26  to  28  per  cent. 

The  quantity  of  oil  yielded  by  any  seed  subjected  to  the  press  is 
always  considerably  less  than  that  which  it  contains,  and  the  oil  re- 
tained in  the  cake  appears  to  be  in  larger  proportion  as  the  starch, 
the  woody  tissue,  and  the  albuminous  matters  are  more  abundant. 
Thus  maize,  or  Indian  corn,  which  contains  from  8  to  10  per  cent 
of  fluid  oil,  gives  mere  traces  of  its  presence  under  the  press. 

The  oily  and  fleshy  fruits,  such  as  those  of  the  olive  and  the  palm, 
yield  a  considerable  quantity  of  oil.  In  the  southern  countries  of 
Europe,  particularly  those  which  are  so  well  protected  that  their 
olive-trees  escaped  the  severe  winter  of  1789,  as  many  as  about 
816  J  lbs.  of  oil  per  acre  are  obtained,  with  proper  care.  The  trees 
which  were  killed  during  this  memorable  winter  sprouted  again 
from  the  roots,  and  at  the  present  day  yield  from  about  one  quarter 
to  one  half  the  above  quantity,  according  to  the  spaces  left  between 
them,  which  vary  considerably.  Under  similar  circumstances  in 
regard  to  climate,  it  will  readily  be  understood,  that  the  quantity  of 
produce  will  be  influenced  by  the  quantity  of  manure  put  into  the 
ground.  In  some  countries  the  olive  is  never  manured,  save  indi- 
rectly ;  that  is  to  say,  the  ground  between  the  trees  is  only  manured 
with  a  view  to  another  crop,  which  is  grown  between  them  ;  in  other 
countries,  again,  in  the  neighborhood  of  Marseilles,  for  instance,  it 
is  the  practice  to  manure  the  olive  plantations,  directly,  every  three 
or  fonr  years. 

The  olive  enjoys  remarkable  longevity  ;  I  have  mentioned  one 
more  than  seven  centuries  old,  and  the  term  of  the  tree's  existence 
appears  only  to  be  limited  by  the  severe  winters  which  cause  it  to 
die,  from  time  to  time.  The  produce  must  of  course  depend  upon 
the  age  of  the  trees  which  compose  a  plantation.  Up  to  eleven 
years,  M.  Gasparin  shows  that  an  olive-tree  still  remains  all  but  un- 


140  OIL. 

prodQctive ;  and  that  the  capital,  and  the  interest  upon  the  capital 
expended  in  this  husbandry,  must  necessarily  exceed  the  value  of 
the  produce  up  to  the  thirtieth  year.  Yet  there  are  soils  which  are 
favorable  to  the  olive,  and  which  are  useful  for  nothing  else ;  a  hole 
in  a  rock  suffices  it,  if  the  climate  be  favorable  and  it  receive  a 
praper  dose  of  manure.  But  the  grand  cause  of  the  disadvantages 
attending  the  cultivation  of  the  olive,  in  France,  is  connected  with 
the  periodical  occurrence  of  severe  winters,  which  kill  it ;  in  an 
interval  of  one  hundred  and  twelve  years,  from  1709  to  1821,  the 
olive  plantations  have  suffered  three  great  mortalities,  which  give  a 
mean  duration  of  about  forty  years  to  each  planting. 

The  cocoa-nut-tree  is  one  of  those  which  yields  the  largest  quan- 
tity of  oil  with  the  least  labor.  The  tree  grows  vigorously  in  all  hot 
countries,  at  no  great  distance  from  the  sea-shore  ;  wherever  the  tem- 
perature is  from  78°  to  82°  Fahr.,  there  the  cocoa-nut  thrives.  It  is 
also  found  on  the  banks  of  great  rivers  ;  and  the  common  practice  in 
planting  the  cocoa-nut  is  to  put  a  little  salt  in  the  hole.  When  trans- 
planted far  from  the  banks  of  rivers,  it  thrives  best  in  the  neighborhood 
of  human  habitations,  which  has  led  the  Indians  to  say  that  the 
cocoa-nut-tree  loves  to  hear  men  talking  under  its  shade.  It  is  a 
tree  which  requires  a  soil  impregnated  with  saline  substances,  and 
these  are  never  wanting  near  the  habitations  of  man.  The  tree 
bears  its  first  flowers  at  the  age.of  four  years ;  it  produces  fruit  the 
following  year,  and  continues  to  fructify  until  it  is  eighty  years  old. 
The  spikes  generally  bear  about  twelve  cocoa-nuts,  and  the  number 
of  nuts  yielded  by  a  tree  in  the  course  of  a  year  may  be  taken  at 
about  fifty,  which  will  yield  about  four  litres,  or  rather  more  than 
seven  pints  of  oil.  Somewhere  about  ninety  trees  are  generally 
found  upon  the  acre  of  land,  and  these  are  capable  of  yielding  about 
825  lbs.  of  oil  annually* 

The  cocoa-nut-tree  must,  therefore,  be  regarded  as  among  the 
most  productive  in  oil,  and  also  as  the  plant  which  requires  the  least 
outlay  in  its  cultivation.  Many  species  of  palm  yield  oils  of  a  very 
agreeable  flavor  for  the  table,  and  the  produce  of  all  answers  admira- 
bly for  the  manufacture  of  soap.  In  the  same  proportion  as  agri- 
cultural industry  extends  in  the  equatorial  regions  of  the  globe,  will 
the  production  of  palm-oils  increase,  and  this  must  necessarily  in- 
fluence the  cultivation  of  the  olive  in  a  very  serious  way.  The  cul- 
tivation of  the  tree  being  already  threatened  in  Europe  by  that  of 
the  mulberry,  and  the  prodigious  extension  in  the  trade  in  palm-oil 
upon  the  coasts  of  Africa  in  the  course  of  the  last  few  years,  justify 
this  conclusion.  In  1817,  palm-oil  was  considered  as  among  the 
list  of  mere  medicinal  substances.  At  this  period  a  London  perfumer 
thought  of  making  it  into  a  soap  for  the  toilet-table.  From  this  time 
it  became  the  staple  of  a  bartering  trade,  which  has  been  by  so  much 
the  more  profitable  to  the  nations  engaged  in  it,  as  the  purchase  is 
always  effected  by  manufactured  articles,  such  as  cotton  and  wool 
len  goods,  hardware  and  crockery,  arms,  powder,  &c.     The  future 

*  Codazzi.  Remmen  de  la  Geografia  de  la  Venezuela,  p.  133. 


ESSENTIAL    OILS.  141 

extent  of  this  traffic  may  be  imagined  when  it  is  known  that  in  1817 
the  importation  of  palm-oil  into  England  did  not  much  exceed 
140,000  lbs.,  and  that  in  1836  it  exceeded  70,000,000  lbs  !  In  tak- 
ing an  acre  of  surface  for  unity,  I  find  that  on  an  average  the 

Spring  oleaginous  plants  yield 3201bs.  of  oil. 

Winter  oleaginous  plants 534        " 

The  olive  (south  of  Europe) 534        " 

The  Palm  (America) 801        " 

OF  ESSENTIAL  OILS. 

Aromatic  plants  owe  the  odors  which  characterize  them  to 
certain  volatile  principles,  which  by  reason  of  certain  properties 
which  they  have  in  common  with  fat  oils,  such  as  insolubility  in 
water,  solubility  in  ether  and  alcohol,  inflammability,  &c.,  are  gen- 
erally designated  as  essential  oils.  They  are  met  with  in  all  parts 
of  plants  ;  but  in  one  plant  the  oil  is  principally  found  in  the  flower, 
in  another  in  the  leaves,  in  another  in  the  bark,,  <fec.  It  sometimes 
happens  that  diflferent  parts  of  the  same  plant  contain  oils  of  different 
kinds.  From  the  orange-tree,  for  instance,  three  distinct  oils  are 
obtained,  as  the  flower,  the  leaf,  or  the  rind  of  the  fruit  is  treated. 
In  some  cases  the  volatile  principle  is  so  thoroughly  imprisoned  in 
the  vegetable  cells,  that  drying  does 'not  dissipate  it;  in  others,  as 
in  the  greater  number  of  flowers,  the  oil  is  formed  on  the  surface, 
and  is  volatilized  immediately  after  its  formation. 

Essential  oils  are  less  volatile  than  water ;  nevertheless  they  rise 
with  the  vapor  of  water,  and  it  is  by  distillation  that  they  are  gen- 
erally extracted.  The  plant  is  put  into  a  still  or  alembic  containing 
water,  and  heat  is  applied  :  the  vapor  formed  is  condensed  in  the 
receiver,  and  the  essence,  by  reason  of  its  less  density,  is  found 
swimming  on  the  surface  of  the  water  which  has  been  distilled. 
Some  volatile  oils  are  obtained  by  pressure,  those  of  the  citron  and 
bergamotte,  for  example. 

The  volatile  principles  of  plants  present  somewhat  varied  physical 
properties.  They  are  generally  limpid  and  lighter  than  water  ;  yet 
there  are  some  which  are  more  dense,  and  some,  such  as  camphor, 
which  are  solid.  With  reference  to  their  composition,  volatile  oils 
may  be  divided  into  three  classes ;  1st.  Oils  composed  entirely  of 
carbon  and  hydrogen.  2d.  Oils  composed  of  carbon,  hydrogen 
and  oxygen.  3d.  Essential  oils  containing  sulphur  ;  in  addition  to 
which,  the  essential  oil  of  mustard  seed  contains  azote. 

The  essential  oils  undergo  a  change  by  long  contact  with  the  air  : 
they  absorb  oxygen,  an  i  many  of  them  become  acidified  ;  under  the 
influence  of  this  gas,  the  oil  of  bitter  almonds  is  changed  into  ben- 
zoic acid,  the  oil  of  cinnamon  into  cinn-amic  acid ;  in  a  general 
way,  acetic  acid  is  produced.  The  volatile  oil  obtained  from  any 
plant  almost  always  contains  two  distinct  principles,  which  may  be 
separated  by  careful  distillation  ;  one  of  these  principles  is  a  car- 
buret of  hydrogen,  the  other  an  oxygenated  oil.  Camphor  is  com- 
bined vyith  essential  oils  in  many  plants  of  the  labiate  family.     It 


142  RESINS. 

exudes  from  certain  laurels  ;  it  is  from  the  Laurus  camphora  that 
all  the  camphor  of  commerce  is  extracted  in  the  East,  the  extraction 
being  effected  precisely  by  the  same  process  as  other  essential  oils. 
The  chips  of  tiie  Laurus  cam-phora  are  put  into  iron  stills,  surmount- 
ed by  earthenware  capitals,  in  the  inside  of  which  a  number  of 
ropes  made  of  rice-straw  are  stretched ;  the  camphor  rises  and  ia 
condensed  on  the  surface  of  these  cords  in  the  state  of  a  gray  pow 
der ;  it  is  refined  by  sublimation. 
According  to  M.  Dumas,  camphor  contains  : 

Carbon ...       79.2 

Hydrogen 10.4 

Oxygen 10.4 

100.0 

OF   RESIN. 

Essential  oils  almost  always  hold  certain  substances  in  solution 
which  make  them  viscid  or  sticky.  The  balsams  which  exude  from 
the  bark  of  certain  trees  are  nothing  more  than  solutions  of  resin  in 
essential  oils.  When  the  volatile  oil  has  been  dissipated  by  evapo- 
ration, the  resin  remains  in  the  solid  state.  There  is  further  a  nat- 
ural relation  in  point  of  constitution  between  essential  oils  and  resins. 
The  greater  number  of  essences  absorb,  as  we  have  said,  oxygen 
from  the  atmosphere,  and  by  this  absorption  they  become  thick,  and 
are  changed  into  resins ;  so  that  in  one  case  the  resin  may  be  a 
product  of  the  oxidation  of  an  essential  oil,  in  another  it  may  merely 
be  set  at  liberty  by  the  dissipation  of  the  essence  which  held  it  in 
solution. 

The  resins  constitute  friable,  or  soft  solids.  They  are  fusible, 
extremely  inflammable,  and  fixed.  The  resins  are  inodorous  when 
pure  :  any  odor  which  particular  resins  possess  is  generally  attrib- 
uted to  the  essential  oil  which  they  still  retain.  The  resins  are  in- 
soluble, or  very  sparingly  soluble  in  water ;  some  of  them  dissolve 
readily  in  alcohol  and  in  ether,  and  there  are  some  also,  such  as 
copal,  which  are  only  soluble  in  very  small  quantity.  Some  resins 
show  acid  reaction  ;  they  combine  with  bases,  neutralizing  them. 
The  greater  number  of  resinous  matters  obtained  from  plants  are 
regarded  by  chemists  as  mixtures  of  several  particular  resins,  the 
study  of  which  is  not  ye*,  much  advanced.  Some  resins  are  much 
employed  in  the  arts,  such  as  colophony  and  copal,  &c.  Several 
balsams  are  also  in  familiar  use,  particularly  as  medicines,  such  as 
the  balsam  of  tolu,  balsam  of  copaiba,  &c. 

Colophony,  or  rosin,  is  extracted  from  different  kinds  of  the  genus 
Pinus.  In  the  Landes,  or  sandy  plains  of  Bordeaux,  it  is  the  mari- 
time pine  which  yields  it.  When  the  tree  is  from  thirty  to  forty 
years  of  age,  incisions  are  made  in  the  trunk,  beginning  at  the  lower 
part,  two  or  three  times  a  week,  ,and  these  are  continued  to  the 
height  of  from  6  to  10  feet  from  the  ground  ;  the  last  notch  general.. 
ly  reaches  this  height  about  four  years  after  the  tree  has  been  notch- 
ed for  the  first  time.  After  this  a  new  series  of  notches  is  be^un 
pa  the  opposite  side,  setting  out  from  the  ground  as  before,  and  in 


VEGETABLE  WAX.  143 

this  way  the  whole  circumference  of  the  tree  finally  presents  a  series 
of  notches,  so  that  a  tree  will  continue  to  yield  turpentine  during  a 
period  of  sixty  years.  The  turpentine  which  exudes  from  the 
notches  is  collected  in  a  hole  dug  in  the  ground. 

Crude  turpentine  always  contains  a  quantity  of  intermixed  foreign 
matters,  earth,  stones,  leaves,  &c.  It  is  purified  by  being  melted,  and 
filtered  hot  through  a  bed  of  straw.  By  distillation  it  is  separated  into 
essential  oil,  which  is  condensed  in  the  receiver,  and  colophony,  or 
rosin,  which  remains  in  the  still.  From  250  lbs.  of  turpentine  30  lbs. 
of  essence  and  220  lbs.  of  rosin  are  generally  obtained. 

Copal  is  the  produce  of  a  tree  which  is  somewhat  common  in 
Madagascar,  and  which  M.  Perrotet  has  determined  to  be  the  Hy- 
menaa  verrucosa.  The  balsam  or  sap  which  exudes  from  the  bark 
solidifies  by  contact  with  the  air,  and  the  resin  is  gathered  in  the 
state  in  which  it  is  met  with  in  commerce. 

CAOUTCHOUC. 

The  caoutchouc  which  we  have  mentioned  as  forming  a  constituent 
in  the  sap  of  certain  trees  possesses  some  properties  which  assimi- 
late it  with  the  resins.  Thus  pure  ether,  free  from  alcohol,  dis- 
solves it.  The  greater  number  of  the  essential  oils  also  dissolve  it, 
particularly  when  hot.  It  is  a  solution  of  Indian  rubber  in  rectified 
coal-tar  oil  or  naphtha,  which  is  now  used  so  extensively  for  making 
stuflfs  water-proof.  According  to  Faraday  pure  caoutchouc  is 
composed  of : 

Carbon 87.2 

Hydrogen 12.8 

■  100 

VEGETABLE    WAX. 

Some  plants  produce  a  considerable  quantity  of  a  substance  which 
bears  a  great  resemblance  to  beeswax,  and  which  in  some  of  its 
properties  approaches  fatty  bodies.  Proust  discovered  that  vegeta- 
ble wax  formed  part  of  the  green  fecula  of  a  great  number  of  vege- 
tables. In  the  common  cabbage  it  occurs  in  large  quantity.  It  is 
often  met  with  forming  a  varnish  on  the  surface  of  leaves,  fruit,  and 
barks  ;  the  substance,  however,  is  far  from  being  identical ;  it  al- 
most always  results  from  the  combination  of  several  distinct  princi- 
ples which  have  not  yet  been  sufficiently  studied,  but  among  which 
there  are  obviously  some  true  fatty  substances,  that  is  to  say,  bodies 
capable  of  saponification,  and  matters  analogous  to  the  resins.  I 
shall  here  mention  a  few  of  the  vegetable  waxes  which  are  best 
known. 

Wax  of  the  palm.  This  is  the  product  of  the  Ceroxylon  andicola, 
which  is  very  abundant  on  the  central  Cordillera  of  New  Grenada. 
I  believe  that  I  met  with  the  Lower  limit  of  the  ceroxylon  upon  the 
holders  of  the  torrent  of  Tochecito,  at  the  height  of  7500  feet  above 
the  level  of  the  sea,  and  I  followed  it  to  an  absolute  elevation  of 
about  8500  feet.     The  extreme  mean  temperatures  comprised  be- 


144  VEGETABLE  WAX. 

tween  these  two  limits  may  be  valued  at  from  IP  to  18"  cent. , 
51.8°  to  64.4°  Fahr.  Towards  the  superior  limit,  the  ceroxylon  is 
exposed  to  a  cold  during  tiie  night,  which  approaches  the  freezing 
point  of  water ;  it  is  therelbre  frequently  met  with  in  company  with 
the  great  oak  of  America,  whose  climate  it  stands  very  well. 

The  Indians  obtain  the  wax  by  scraping  the  bark  of  the  palm : 
the  scrapings  are  then  boiled  in  water ;  the  wax  swims — without, 
however,  melting  ;  it  is  merely  softened,  and  the  impurities  which  it 
contains  are  deposited.  The  matter  thus  purified  is  formed  into 
balls  and  set  to  dry  in  the  sun.  It  is  with  this  substance,  to  which, 
however,  a  small  quantity  of  fat  is  often  added  to  render  it  less  brit- 
tle, that  the  loaves  of  wax  and  the  candles  of  the  country  are  form- 
ed. After  it  has  been  melted,  the  cera  de  palma  is  of  a  deep  yellow 
color,  slightly  translucid,  as  brittle  as  resin,  and  presenting  a  waxy 
fracture  well  characterized.  Its  melting  point  is  a  little  above  that 
of  boiling  water.  Boiling  alcohol  dissolves  it  readily  ;  in  cooling, 
the  solution  sets  into  a  gelatinous  mass.  Ether  dissolves  it,  as  do 
the  alkalies  also. 

The  wax  of  the  palm  consists  of  two  principles ;  one,  fusible 
above  the  temperature  of  the  boiling  point  of  water,  has  all  the 
physical  properties  of  beeswax  ;  the  other  has  the  properties  of 
resin.  The  composition  of  these  substances  upon  analysis  appears 
to  be: 

Wax.  Resin. 

Carbon 81.6  83.7 

Hydrogen 13.3  11.5 

Oxygen 5.1  4.8 

100  100 

Wax  of  the  Myrica  cerifera.  This  wax  is  procured  by  boiling 
the  fruit  of  several  species  of  myrica  in  water.  The  tree  is  ex- 
tremely common  in  Louisiana  and  the  temperate  regions  of  the 
Andes.  The  fruit  yields  as  much  as  25  per  cent,  of  wax,  and  a 
single  shrub  will  yield  from  24  to  30  lbs.  of  berries  per  annum.  The 
crude  wax  is  green,  brittle,  and,  to  be  made  into  candles,  requires 
the  addition  of  a  certain  quantity  of  grease.  According  to  M.  Che- 
vreul  the  wax  of  the  myrica  is  saponifiable. 

Wax  of  the  sugar-cane.  The  sugar-cane,  particularly  the  violet 
variety,  is  covered  with  a  powder  or  bloom  of  a  waxy  nature,  which 
melts  at  the  temperature  of  82"  cent.  (180'  Fahr.)  This  wax  is  so 
hard  that  it  can  be  pulverized  ;  it  may  be  made  into  candles,  which, 
for  the  brilliancy  of  their  light,  are  not  inferior  to  those  of  sperma- 
ceti. M.  Avequin,  who  directed  attention  to  this  subject,  found  by 
his  experiments  that  a  hectare  (nearly  2j  acres  English)  of  the 
violet  cane  would  furnish  nearly  200  lbs.  of  wax.  This  wax  is 
entirely  soluble  in  boiling  alcohol ;  ether  does  not  dissolve  it  in  the 
cold.  It  appears  to  constitute  a  perfectly  defined  immediate  vege- 
table principle,  the  composition  of  which,  according  to  M.  Dumas 
U  the  following : 

Carbon 81.4 

Hydrogen 14.1 

Oxygen 4.5 

100 


COLORING  PRINCIPLES.  145 


CHLOROPHYLLE. 


The  green  matter  which  colors  the  leaves  of  vegetables  is  so 
designated.  The  attempts  which  have  been  made  to  isolate  this 
matter,  render  it  probable  that  it  is  somewhat  of  the  nature  of  the 
vegetable  waxes.  Pelletier  and  Caventou  endeavored  to  procure  it 
by  treating  with  cold  alcohol,  the  pulp  remaining  after  expressing 
all  the  juices  from  the  leaves  of  various  herbaceous  plants.  By 
evaporation  of  the  alcoholic  liquor,  a  substance  of  a  deep-green  color 
was  obtained,  which  is  chlorophylle,  a  matter  soluble  in  ether,  in  al- 
cohol, the  oils,  and  the  alkalies.  Heated,  it  softens  and  is  decom- 
posed before  it  melts.  Acetic  acid  dissolves  it  in  very  appreciable 
quantities,  so  do  the  sulphuric  and  hydrochloric  acids  ;  w^ater  precipi- 
tates it  from  these  acid  solutions.  Berzelius  says  that  chlorophylle 
exists  only  in  very  small  quantity  in  plants,  the  leaves  of  a  large  tree 
will  not  perhaps  contain  more  than  about  100  grains. 

OF  COLORING  MATTERS. 

The  matters  which  color  the  different  parts  of  plants  are  extreme- 
ly numerous  ;  they  present  great  varieties  of  shade,  but  are  in  gen- 
eral derived  from  red,  yellow,  and  green.  It  is  seldom  that  the  col- 
oring matter  of  a  plant  exists  isolatedly  ;  it  is  almost  always  allied 
with  one  or  several  immediate  principles,  which  are  themselves  fre- 
quently colored.  Thus  red  coloring  matters  are  generally  combined 
with  yellow  principles,  which  having  nearly  the  same  properties,  one 
is  with  great  difficulty  separated  from  another. 

Coloring  matters  are  solid,  inodorous,  and  have  little  taste.  Some 
are  soluble  in  water,  others  only  dissolve  in  alcohol  or  in  ether. 
All  combine  with  the  alkalies,  and  several  of  them  unite  intimately 
with  acids ;  the  greater  number  are  powerfully  affected,  undergo  a 
true  destruction,  on  exposure  to  the  sun's  rays,  especially  when  in 
contact  with  moist  air.  It  is  familiarly  known  that  vegetable  tissues 
of  all  kinds,  beeswax,  &c.,  are  bleached  by  exposure  to  the  sun  and 
air ;  a  high  temperature  acts  like  light :  some  vegetable  colors  are 
altered,  bleached,  when  they  remain  exposed  for  a  time  to  a  tem- 
perature of  from  334°  to  424°  Fahr.  The  oxygen  of  the  air,  which 
so  quickly  destroys  certain  colors,  develops  others  under  particular 
circumstances. 

Alkalies  and  acids,  by  uniting  with  vegetable  colors,  almost  al- 
ways modify  their  tints  and  often  change  them  entirely.  Many  blues, 
for  instance,  become  reds,  under  the  agency  of  acids,  greens  or 
yellows  under  that  of  alkalies.  By  neutralizing  the  acid  or  the  al- 
kali, the  color  generally  resumes  its  original  tint. 

Several  substances,  which  are  colorless  in  the  state  in  which  they 
are  formed  in  vegetables,  become  colored  by  the  united  action  of 
oxygen  and  an  alkali,  such  as  orceine,  which  is  oxidated  and  be- 
comes blue  under  the  simultaneous  contact  of  air  and  ammonia. 
The  greater  number  of  vegetable  coloring  matters  are  destroyed 

13 


146  INDlttO. 

and  bleached  by  chlorine.  Many  of  the  same  matters  unite  inti- 
mately with  alumina  and  oxide  of  tin  to  form  lakes,  insoluble  com- 
pounds in  which  the  colors  remain  fixed  ;  thus  a  colored  liquid  often 
becomes  colorless  when  it  is  shaken  with  a  hydrate  of  alumina. 
Charcoal,  in  a  state  of  extreme  subdivision,  acts  like  alumina,  and 
is  a  powerful  discharger  of  colors  in  every-day  use  in  the  arts. 
Coloring  matters  are  generally  ternary  compounds,  though  some  of 
them  also  contain  azote  ;  and  several  of  them  exhihit  the  remarka- 
ble phenomenon,  that  in  undergoing  oxidation  in  contact  with  am- 
monia they  assimilate  the  azote  of  this  alkali.  I  shall  now  indicate 
the  origin  and  the  mode  of  preparing  a  few  of  the  more  important  of 
these  coloring  matters. 

Indigo.  This  substance,  so  essential  in  the  art  of  dyeing,  has  been 
one  of  the  great  staples  of  trade  with  Asia  from  the  most  remote 
times.  For  a  long  while  indigo  was  regarded  in  Europe  as  a  min- 
eral substance  found  in  India :  it  used  to  be  designated  Indian  or  In- 
dia stone,  whence  the  name  of  indigo.  It  was  not  until  after  the  dis- 
covery of  America  that  the  true  nature  of  this  dye-stuff  was  known, 
although  before  this  period  indigo  had  been  made  in  Arabia,  Egypt, 
and  even  in  the  Island  of  Malta. 

Indigo  is  volatile,  so  that  to  obtain  it  pure,  it  is  enough  to  put  a 
small  quantity  into  a  platinum  capsule,  to  cover  it  with  a  lid  and  to 
expose  it  to  heat.  Indigo  is  volatilized  in  the  state  of  violet-colored 
vapor,  and  collects  in  crystals  upon  the  middle  part  of  the  sides  of 
the  capsule.  Indigo  gives  nothing  to  water  or  to  ether.  Alcohol 
takes  up  a  very  small  quantity  of  it ;  concentrated  sulphuric  acid 
dissolves  and  modifies  it. 

All  bodies  greedy  of  oxygen  appear  to  reduce  or  deoxidize  this 
coloring  principle ;  it  changes  to  a  yellow,  and  becomes  soluble  in 
water  in  contact  with  alkalies ;  by  exposing  the  alkaline  liquor  charg- 
ed with  the  uncolored  indigo  to  the  air,  it  absorbs  oxygen  rapidly, 
and  the  indigo  becomes  insoluble  and  is  precipitated  with  its  original 
blue  color.  It  is  most  easy,  as  said,  to  disoxidize  indigo  ;  it  is  suf- 
ficient t'j  bring  it  into  contact  with  hydrogen  gas  in  the  nascent  state, 
a  condition  which  is  readily  secured  by  throwing  iron  or  zinc  filings 
into  water  containing  the  coloring  matter  previously  dissolved  in 
sulphuric  acid.  The  disengagement  of  the  hydrogen  has  scarcely 
commenced  before  the  deep-blue  color  of  the  solution  declines  in 
intensity,  and  by  and  by  it  becomes  of  a  very  pale  gray.  When  the 
discharge  of  color  is  completed,  and  no  more  hydrogen  is  disengaged, 
the  colorless  indigo  begins  to  react  upon  the  air,  it  absorbs  oxygen, 
becomes  again  oxidized,  and  by  and  by  the  liquid  has  resumed  its 
deep  blue.  This  property  of  indigo  of  becoming  soluble  in  alkaline 
solutions  under  the  influence  of  disoxidizing  bodies,  is  taken  advan- 
tage of  in  our  laboratories  to  obtain  indigo  in  a  state  of  purity,  and 
in  the  arts  to  prepare  a  dyeing  liquid.  If  a  mixture  be  made  of  15 
parts  of  the  indigo  of  commerce  reduced  to  fine  powder,  10  parts  of 
the  sulphate  of  the  protoxide  of  iron,  15  parts  of  lime,  and  60  parts 
of  water,  and  it  be  left  for  several  days  in  a  closed  vessel,  a  color 
less  liquid  is  obtained.    The  liquid  decanted  and  exposed  to  the  air 


INDIGO.  147 

deposites  the  whole  of  its  indigo  after  a  time.  It  is  with  similar  in- 
gredients that  the  dyer  prepares  his  bath  for  blue  colors.  It  is  into 
the  alkaline  liquor  so  prepared  that  the  stuff  to  be  dyed  is  dipped  ;  it 
is  then  hung  up  in  the  air,  where  it  soon  becomes  blue ;  it  is  re- 
dlpped  :ind  re-exposed  again  and  again,  until  it  has  acquired  the 
depth  of  tint  required,  after  which  it  is  washed.  The  indigo,  re- 
generated bj  the  action  of  the  air,  remains  fixed  in  the  stuff,  and 
proves,  as  all  the  world  knows,  one  of  the  most  solid  of  colors. 

Chemists  are  not  agreed  as  to  the  true  nature  of  colorless  indigo 
which  may  be  obtained  in  the  solid  state.  Some  regard  it  as  indigo 
disoxidized,  others  as  indigo  hydrogenized.  On  the  latter  supposi- 
tion, the  hydrogen  fixed  would  be  derived  from  the  water  decom- 
posed, the  oxygen  of  which  would  be  transferred  to  the  bodies  greedy 
of  this  element,  which  are  brought  into  play.  The  latter  of  these 
views  appears  to  have  the  ascendant  at  the  present  time.  However 
this  may  be,  the  following  is  the  composition  of  indigo  in  each  of 
its  states,  as  determined  by  M.  Dumas : 

Blue  Indi|ro.  White  Indiro. 

Carbon 73.1  73.0 

Hydrogen 4.0  445 

Azote 10.8  10.6 

Oxygen 12.1  11.9 

100.0  100.0 

The  plants  which  have  hitherto  been  cultivated  for  the  production  of 
indigo  with  any  profit  are  not  numerous ;  they  belong  to  the  genera 
Indigo/era,  Isatis  et  Nerivm ;  it  is  the  genus  Indigo/era  which  is  most 
generally  cultivated,  and  the  species  designated  argentea  is  found 
to  be  the  most  profitable.  M.  Chevreul  has  ascertained  that  in  the 
living  plant  the  indigo  is  not  colored,  and  that  it  is  consequently 
during  its  extraction  that  it  becomes  blue.  The  experiments  of  M. 
Pelletier  upon  the  Polygonum  tinctorium  have  confirmed  the  old  re- 
searches of  M.  Chevreul.  After  having  dried  a  leaf,  Pelletier  di- 
gested it  with  ether  in  a  closed  flask.  The  whole  of  the  chlorophylh 
was  dissolved,  and  the  leaf  became  completely  blanched  ;  by  expo 
sing  it  afterwards  to  the  air,  it  turned  blue  if  it  contained  indigo. 

In  the  republic  of  Venezuela,  where  I  had  an  opportunity  of  study 
ing  the  cultivation  of  the  indigo-bearing  plants,  I  saw  that  those  soil;- 
were  preferred  which  were  light  and  susceptible  of  irrigation,  a 
condition  indeed  which  seems  to  me  all  but  indispensable  to  the  pro- 
fitable exercise  of  agriculture  within  the  tropics.  Indigo  requires  a 
warm  climate ;  at  an  elevation  of  about  3250  feet  English  above 
the  level  of  the  sea,  where  the  mean  temperature  is  not  more  than 
from  72°  to  75°  Fahr.,  the  indigo  husbandry  cannot  be  carried  on  with 
advantage.  Nevertheless,  the  Indigofera  sylvestris  is  met  with  at  an 
elevation  of  about  4900  feet  above  the  level  of  the  sea;  but  the  at- 
tempts that  have  been  made  to  obtain  coloring  matter  from  the  plant 
have  proved  fruitless.  In  the  valley  d'Aragua,  where  the  best  plan- 
tations are  met  with,  the  plant  is  sowed  in  lines,  the  holes  destined 
to  receive  the  seed  being  about  If  inch  in  depth,  and  somewhat 
more  than  25  inches  apart.     A  pinch  of  seed  is  dropped  into  each 


148  INDIGO. 

hole,  and  is  covered  with  a  little  earth.  The  sowing  takes  place  in 
soils  that  are  moist  but  well  drained,  or  in  situations  generally  which 
have  no  system  of  irrigation  at  the  period  of  the  first  rains.  The 
seeds  shoot  in  the  course  of  the  first  week  ;  hoeing  is  performed  in 
the  course  of  the  month.  The  first  cutting  takes  place  when  the 
plant  is  coming  into  flower  ;  from  fifiy  to  sixty  days  generally  inter- 
vene between  the  sowing  and  this  cutting ;  but  the  time  necessary 
for  the  development  of  the  leaves  depends  of  course  upon  the  cli- 
mate. In  the  neighborhood  of  Maracaibo,  where  the  mean  tempera- 
ture is  about  78°  Fahr.,  the  gathering  does  not  take  place  before  the 
third  month.  The  second  cutting  is  performed  from  45  to  50  days 
after  the  first ;  and  in  this  way  several  successive  crops  are  obtained, 
until  it  is  seen  that  the  plant  begins  to  degenerate.  In  good  soils 
the  indigo  will  last  for  two  years  ;  in  soils  of  inferior  quality  the 
crop  is  generally  annual. 

The  indigo  harvest  is  immediately  transported  to  tanks  or  large 
rectangular  reservoirs  built  of  masonry,  and  disposed  on  different 
levels,  the  superior  reservoir  or  steeping  tank  being  much  larger 
than  the  two  others.  In  the  valley  d'Aragua,  there  are  some  which 
are  upwards  of  20  feet  long  by  15  feet  wide,  and  20  inches  in  depth. 

The  second,  or  mashing  tank,  is  narrower  and  deeper  than  the  for- 
mer. The  third  reservoir,  or  depositing  tank,  receives  the  liquor 
from  the  mashing  tank,  and  in  it  the  indigo  subsides.  In  some  manu- 
factories the  third  tank  is  not  used,  the  deposition  taking  place  in  the 
mashing  tank  itself. 

The  leaves,  as  the  name  implies,  are  thrown  into  the  steeper, 
covered  with  w^ater,  and  kept  down  by  planks  loaded  with  stones  ; 
fermentation  soon  begins,  and  is  allowed  to  continue  during  about 
eighteen  hours ;  and  in  the  management  of  this  first  operation  lies 
much  of  the  art  of  the  indigo-maker.  By  continuing  it  too  long 
some  portion  of  the  coloring  matter  is  destroyed  ;  by  stopping  it 
prematurely,  a  quantity  of  indigo  is  left  in  the  leaves.  The  fermen- 
tation judged  to  be  sufficiently  advanced,  the  liquor  is  run  off"  into 
the  battery,  and  vigorously  stirred  until  the  grain  is  deposited.  The 
fluid  is  then  either  let  into  the  subsider,  or  left  in  the  battery,  and 
the  deposition  is  complete  at  the  end  of  about  twenty  hours ;  the 
supernatent  fluid  is  drawn  off",  and  the  indigo  paste  is  scooped  out 
and  placed  upon  cloths  to  drain.  When  sufficiently  firm,  it  is  divided 
into  lumps,  and  these  are  set  in  the  shade  to  dry.  In  the  valley 
d'Aragua  it  is  estimated  that  with  a  good  soil  and  careful  manage- 
ment, each  hectare  of  surface  will  yield  280  lbs.  of  marketable  indi- 
go,* which  is  at  the  rate  of  about  112^-  lbs.  per  English  acre. 

In  Carolina  the  cultivation  of  indigo  appears  to  be  much  less  pro- 
ductive than  in  the  equinoctial  regions,  and  the  produce  is  of  inferior 
quality.  There  they  sow  in  drills  in  the  commencement  of  the 
rainy  season  which  follows  the  vernal  equinox,  and  the  first  crop  is 
gathered  about  the  beginning  of  July  ;  the  second  is  secured  two 
months  afterwards,  and  when  the  autumn  is  mild,  a  third  but  insig* 

•  Cadozzi,  Resumen  de  la  Geografia  de  Venezuela,  p.  144. 


INDIGO.  149 

nificant  gathering  takes  place  at  the  end  of  September.  One  negro 
Is  allowed  to  be  able  to  work  nearly  two  acres  and  a  half  of  ground, 
trom  wiuch  about  160  lbs.  of  indigo  are  obtained. 

i\^  the  East  Indies,  upon  the  Coromandel  coast,  the  growth  of  in- 
ligo  tak<;s  place  upon  sandy  soils  which  are  not  irrigated,  and  in 
which  vegetation  is  only  possible  during  the  rainy  season.  The 
loamy  soils  that  admit  of  being  irrigated  are  almost  always  reserved 
for  the  growth  of  rice.  Immediately  after  the  rains  have  set  in,  in 
December,  the  land  receives  two  superficial  ploughings  ;  the  indigo 
is  sown  broad-cast,  and  the  seed  is  harrowed  in  by  dragging  a  fagot 
of  bamboos  over  the  surface,  or  by  treading  in  by  means  of  a  flock 
of  sheep.  The  first  and  principal  gathering  takes  place  in  March  ; 
any  other  crop  that  may  be  won  is  purely  casual,  and  entirely  de- 
pendent on  the  rain  that  falls.  The  crop  rarely  fails  to  feel  the 
effects  of  the  droughts  which  so  frequently  take  place  upon  the 
Coromandel  coast.  It  is  never  abundant,  and  the  plants  have  little 
vigor.  The  harvest  takes  place  after  the  flowering  season.  The 
crop  is  dried  in  the  sun  ;  the  plant  is  then  beaten  with  switches,  by 
which  the  leaves  are  detached  from  the  stems,  after  which  hey  are 
exposed  anew  to  the  sun  to  secure  their  being  perfectly  dry.  They 
are  then  reduced  to  coarse  powder,  and  handed  over  to  the  indigo- 
maker,  for  in  India  the  planter  is  never  himself  the  manufacturer 
of  the  dye-stuff". 

On  the  coast  of  Coromandel,  indigo  is  always  extracted  from  the 
dried  leaves,  which,  bruised  and  broken,  are  infused  in  three  or  four 
times  their  bulk  of  cold  water  during  two  or  three  hours  ;  the  infu- 
sion is  then  filtered  through  a  loose  stuff  made  of  goat's  hair  ;  the 
filtered  liquor  is  beaten  for  two  hours,  and  after  this  about  five  gal- 
lons of  lime-water  are  added  for  every  100  lbs.  of  dried  leaves  ;  the 
mixture  is  stirred,  and  then  left  to  settle.  When  the  deposite  has 
formed,  the  supernatent  liquor  is  drawn  off",  the  sediment  is  washed 
with  a  little  boiling  water,  and  being  thrown  upon  a  cloth,  the  indigo 
is  drained  and  dried.  It  is  then  pressed,  and  the  paste  is  cut  into 
cubical  lumps  which  are  thoroughly  dried  in  the  air,  and  of  which 
each  weighs  nearly  3  ounces. 

In  the  Indian  method  of  manufacturing  indigo,  all  is  accomplished, 
as  appears,  without  fermentation.  This  indigo  is  little  esteemed  in 
commerce  ;  it  is  heavy,  of  a  pale  blue,  without  much  of  the  coppery 
aspect,  rough  on  the  broken  surface,  and  presents  here  and  there 
white  points  and  vegetable  debris.  An  acre  of  land  on  the  Coro- 
mandel coast  will  produce  from  48  to  49  lbs.  of  indigo  annually. 

In  spite  of  the  high  price  of  indigo,  so  small  a  quantity  would 
scarcely  cover  the  cost  of  production,  were  not  the  wages  of  the 
Indian  laborer  exceedingly  low.  The  whole  expense  of  producing  a 
kilogramme,  or  S/^  ^^s.  avoird.  of  indigo,  according  to  M.  Plague, 
amounts  to  3  francs,  20  cents,  or  about  2s.  8d. 

The  cultivation  of  the  indigo  plant  has  been  attempted  several 
times-in  the  south  of  Europe,  particularly  in  Spain  and  Italy. 
There  is  no  doubt  but  that  indigo  may  be  grown  in  Europe  in  those 
situations  where  for  three  or  four  months  of  the  year  the  tempera- 


160  ORCHIL. 

ture  is  tiuly  tropical ;  but  it  seems  probable  that  indigo  can  never 
be  advantageously  introduced  into  the  agriculture  of  temperate  coun- 
tries. 

Before  indigo  was  so  extensive  an  article  of  commerce  as  it  is 
now,  the  south  of  France  used  to  furnish  almost  all  the  marketvS  of 
Europe  with  a  blue  dye,  which  was  the  best  then  known ;  this  was 
woad  or  pastel,  the  produce  of  the  Isatis  tinctoria. 

The  isatis  is  sufficiently  hardy  to  stand  the  cold  of  winter.  In 
the  south  it  is  sown  in  March,  and  the  seed  springs  in  from  eight  to 
ten  days.  When  the  plant  has  five  or  six  leaves,  it  is  hoed  with 
care.  The  crop  is  gathered  when  the  leaves  have  acquired  their 
greatest  size,  when  they  even  begin  to  fade  a  little.  The  prepara- 
tion of  woad  bears  a  certain  resemblance  to  that  of  indigo,  and  need 
not  detain  us  here. 

The  Polygonum  tinctorium  has  of  late  attracted  the  attention  of 
European  cultivators.  The  plant  is  a  native  of  China,  where  it  has 
been  cultivated  from  time  immemorial ;  it  was  brought  into  France 
and  propagated  under  the  care  of  M.  de  Lille.  In  the  course  of 
three  months  the  plant  has  thrown  out  all  its  leaves,  and  in  the  south 
of  France  it  never  fails  to  ripen  its  seeds.  From  some  experiments 
that  have  been  made,  the  leaves  of  the  polygonum  appear  to  contain 
about  the  five-thousandth  of  their  weight  of  indigo,  and  as  the  acre 
of  land  will  yield  between  11,000  and  11,900  lbs.  weight  of  leaves 
the  produce  of  coloring  matter  will  come  to  upwards  of  56^  lbs. 

The  indigo  obtained  from  the  polygonum  by  the  methods  generally 
practised  is  not  always  of  fine  quality.  It  contains  matters  which, 
having  been  dissolved  in  the  water  used  for  maceration,  had  subse- 
quently been  precipitated  M.  Vilmorin  proposed  to  adopt  on  the 
great  scale  and  in  the  manufactory,  the  methods  which  are  used  for 
purifying  indigo  in  the  laboratory,  and  which  consists,  as  we  have 
seen,  in  reducing  colored  and  insoluble  indigo  to  the  colorless  and 
insoluble  state  by  means  of  a  salt  of  the  protoxide  of  iron  in  contact 
with  an  alkali,  and  subsequently  to  restore  its  color,  and  effect  its 
precipitation  by  contact  with  the  oxygen  of  the  air.  It  is  obvious 
that  this  method  is  perfectly  applicable  to  the  treatment  of  the  whole 
of  the  indigoferous  plants,  and  I  believe  that  its  adoption  would  be 
a  great  improvement. 

Orchil.  This  coloring  matter,  of  a  deep  purple,  is  prepared  from 
certain  lichens  or  lung-worts  ;  that  which  is  most  prized  is  the  rocella 
tinctoria,  a  native  of  the  Canaries  and  Cape  de  Verd  islands.  The 
variolaria  dealbata,  the  var.  aspergillia,  and  the  lichen  corallinus, 
which  grow  upon  the  rocks  of  Auvergne,  and  on  the  Alps  and  Pyre- 
nees, yield  a  produce  of  inferior  quality. 

To  obtain  the  orchil,  the  lichens  are  steeped  for  several  days  in 
their  own  weight  of  stale  urine.  Into  the  mixture  about  5  per  cent, 
of  slaked  lime  in  powder,  a  small  quantity  of  arsenious  acid,  and  a 
little  alum,  are  introduced.  Fermentation  is  by  and  by  set  up  in  the 
mass,  which  soon  acquires  the  characteristic  color  of  the  orchil,  but 
the  tint  is  never  complete  until  the  expiration  of  about  a  month. 

Orchil  readily  communicates  its  peculiar  color  to  water  and  to  al« 


ORCHIL.  151 

cohol ;  the  watery  solution,  which  is  of  a  fine,  crimson,  becomes 
colorless  in  a  fnw  days  when  it  is  kept  in  a  flask  hermetically  seal- 
ed ;  it  regains  its  color  by  exposure  to  the  air.  The  color  which  is 
acquired  during  the  manufacture  of  orchil  indicates  that  the  lichens 
which  yield  it  contain  principles  which  are  colorless  in  themselves, 
but  which  possess  the  singular  property  of  becoming  tinted  under 
the  influence  of  oxygen  and  ammonia ;  for  in  the  preparation  of  or- 
chil, the  addition  of  urine  and  of  lime  has  no  other  purpose  beyond 
the  introduction  and  development  of  this  alkaline  base.  This  view 
is  shown  to  be  correct,  moreover,  by  the  facts  brought  to  light  by 
MM.  Heeren  and  Robiquet  in  their  inquiries  into  the  chemical  con- 
stitution of  the  lichens.  These  chemists,  in  fact,  succeeded  in  ex- 
tracting from  several  of  the  lichens  which  yield  orchil  a  variety  of 
colorless  crystalline  principles,  in  particular  orcine,  a  substance 
which  may  be  procured  in  very  regular  quadrangular  prisms,  and 
which  is  soluble  in  water  and  in  alcohol.  The  watery  solution  of 
orcine  mixed  with  ammonia  and  exposed  to  the  air,  becomes  gradu- 
ally of  a  deeper  and  deeper  red  until  it  has  the  color  of  blood.  The 
result  of  this  oxidation  of  orcine  under  the  action  of  ammonia  is  a 
coloring  principle,  orceine,  into  the  constitution  of  which  azote  en- 
ters, an  element  which  formed  no  part  of  orcine  ;  the  analyses  of 
these  two  substances  made  by  M.  Dumas,  show  this  fact  very  dis- 
tinctly : 

Dry  orcine.  Orceine. 

Carbon 67.8  55.9 

Hydrogen 6.5  5,2 

Oxygen 25.7  31.0 

Azote -J 7.9 

100.0  100.0 

The  lichens  furnish  several  other  principles  analogous  to  orcine  in 
their  property  of  acquiring  color  under  similar  circumstances. 

Turnsole.  This  coloring  matter  is  met  with  in  commerce  in  two 
states,  in  mass  and  in  thin  cakes,  and  is  procured  from  various 
lichens  which  have  not  yet  been  accurately  specified  ;  in  any  case 
the  substance  is  obtained  by  a  process  which  differs  little  from  that 
used  in  the  manufacture  of  orchil.  According  to  Mr.  Kane,  the 
coloring  principles  of  turnsole  are  naturally  red  :  they  only  become 
blue  by  combining  with  a  base.  The  coloring  matters  which  pre- 
dominate in  turnsole  are  erythrolitmine  and  azolitmine,  which  are 
united  with  lime,  potash,  and  ammonia,  and  further  mixed  with  a 
considerable  quantity  of  chalk  and  sand.  The  analyses  of  Kane 
show  these  two  substances  to  have  the  following  composition : — 

Erythrolitmine.  Azolitmine. 

Carbon 55.6  49.8 

Hydi-ogen 8.4  5.4 

Oxygen •  36.0     oxygen  and  azote      44.8 

100.0  100.0 

Turnsole  occurs  in  trade  in  the  shape  of  thin  cakes,  made  up  of 
chips,  which  are  colored  by  the  juice  of  chroijophoria  tincloiiaj  a 
plant  of  the  euphorbiaceous  family,  and  of  which  the  dyeing  pro- 
perties appear  to  have  been  known  to  the  eaiJiest  natuialists. 


152  MADDER. 

Madder.  The  root  of  the  madder  plait,  so  commonly  employed 
in  dyeing,  contains  more  than  one  coloring  matter  ;  but  the  most  im 
portant  of  these,  and  that  which  constitutes  the  most  useful  element 
in  the  root,  is  alizarine,  which  was  discovered  by  M.  Robiquet. 

This  substance  is  scarcely  soluble  in  boiling  water,  but  it  is  soluble 
in  alcohol  and  still  more  so  in  ether,  to  which  it  imparts  a  golden 
yellow  color.  Alkaline  liquors  dissolve  it  and  acquire  a  violet  shade 
extremely  agreeable  to  the  eye.  Alizarine  is  sublimed  by  the  action 
of  heat  in  the  form  of  brilliant  red  needles. 

Madder,  {rubia  tinctorum.)  is  a  native  of  the  south ;  but  as  i*. 
stands  the  winter,  it  is  now  cultivated  almost  all  over  Europe  ;  the 
plant  is  propagated  by  seeds,  but  there  are  certain  advantages  in 
using  the  sprouts  which  it  throws  out  in  the  spring,  and  which  read- 
ily take  root.  The  plant  requires  a  friable  soil,  sufficiently  moist 
and  highly  manured  to  receive  it ;  the  soil  must  be  previously 
trenched  or  have  had  a  very  deep  ploughing.  In  the  east  of  France 
the  planting  takes  place  in  April  or  May.  The  sprouts  which  are 
to  be  transplanted  must  be  about  6  inches  long.  When  the  plant 
has  struck  root,  the  ground  is  cleaned,  and  fifteen  or  twenty  days 
afterwards  it  is  hoed  ;  in  the  course  of  the  summer,  several  other 
hoeings  are  required.  In  Alsace,  madder  is  planted  in  rows  and  in 
patches,  a  certain  interval  between  each  patch  being  left,  the  earth 
of  which,  in  the  month  of  March  of  the  following  year,  is  thrown 
over  the  ground  that  is  planted. 

In  the  neighborhood  of  Hagaenau,  madder  occupies  the  ground 
during  two  years  ;  the  crop  is  gathered  about  the  middle  of  Novem- 
ber. In  some  districts  the  plant  remains  in  possession  of  the  soil  for 
five  or  six  years.  It  is  generally  allowed  that  the  amount  of  produce 
increases  with  time  ;  but  in  those  countries,  such  as  Alsace,  where 
the  plant  is  liable  to  be  attacked  by  frost,  it  is  generally  thougnt 
prudent  to  gather  it  at  the  end  of  two  years  ;  the  harvest  is  then 
profitable,  and  in  the  course  of  the  third  or  fourth  or  any  succeeding 
winter,  it  might  run  the  risk  of  such  severe  frost  as  w..ild  destroy  it 
entirely.  In  southern  countries  the  growers  say  that  a  crop  of  the 
fourth  year  exceeds  very  considerably  one  of  the  third  year  ;  but  it 
might  be  made  a  question  whether  the  increase  actually  compensates 
for  the  longer  occupation  of  the  soil.  And  then  when  the  cultivation 
is  too  much  prolonged,  a  species  of  fungus  is  developed  around  the 
root  and  kills  it.  The  crop  of  madder  is  gathered  with  the  hoe,  a 
laborious  and  costly  process  ;  the  roots  are  then  dried  in  stoves  and 
sent  to  the  mill,  so  that  it  is  in  the  state  of  powder  that  madder  is 
met  with  in  commerce. 

In  Alsace,  where  madder  remains  two  years  in  the  ground,  the 
mean  produce  per  acre  is  estimated  at  about  3300  lbs.  of  dried  roots, 
which  is  equal  to  an  annual  crop  of  about  1650  lbs.  In  the  south  of 
France,  the  mean  animal  produce  amounts  to  something  less  thin 
this,  or  to  about  1560  lbs.  ;*  but  the  quantity  has  been  estinated  a  a 
considerably  lower  amount  still. 

•  Db  Gasparin,  Agricultural  Memoirs,  vol.  ii.  p.  2*3. 


SAFFRON.  153 

Besides  its  roots,  madder  yields  an  abundance  of  leaves  which  are 
excellent  forage. 

Reseda  luleola,  or  dyers'  weed,  is  a  plant  in  common  use,  and  owes 
its  properties  as  a  dye-stuff  to  the  presence  of  a  yellow  crystalline 
principle,  luteoline,  discovered  by  M.  Chevreul.  This  substance  is 
soluble  in  ether,  alcohol,  and  alkaline  solutions. 

Dyers'  weed  is  sown  in  autumn,  stands  through  the  winter,  and 
ripens  in  the  month  of  August  following.  The  plant  is  gathered 
when  it  begins  to  turn  yellow,  and  it  is  in  a  marketable  state  after  it 
is  dried.  An  acre  of  land  will  produce  about  1833  lbs.  weight  of 
marketable  dye-weed. 

Saffron.  This  plant  is  cultivated  in  the  south  of  France  and 
in  Austria,  but  appears  to  be  a  native  of  Asia.  Saffron  requires  a 
light  and  yet  fertile  soil  in  order  to  produce  abundantly,  although  it 
may  also  be  cultivated  in  soils  of  middling  quality.  The  ground, 
trenched  one  spit  deep,  is  set  out  with  bulbs  from  an  old  plantation. 
In  the  south  the  transplanting  takes  place  in  the  month  of  June. 
The  first  flowers  appear  towards  the  middle  of  October ;  they  are 
few  during  the  first  year."  They  are  gathered,  and  the  pistils  removed ; 
the  gathering  continues  for  about  a  fortnight.  In  the  course  of  the 
year  which  follows  the  planting,  the  ground  receives  a  surface  dress- 
ing ;  it  is  freed  from  weeds,  and  the  withered  leaves  are  removed. 
The  next  gathering  takes  place  at  the  same  period  as  the  former, 
but  the  flowers  are  now  much  more  abundant,  and  the  same  process 
is  continued  until  the  roots  are  taken  up,  which  they  are  in  France 
at  the  end  of  the  second  year  ;  but  in  Austria  the  culture  is  contin- 
ued for  a  much  longer  period  in  the  same  piece  of  ground.  The 
extraction  of  the  pistils  is  an  occupation  in  which  the  whole  family 
of  the  saffron -grower  take  part,  and  employ  their  evenings  ;  in  the 
course  of  an  evening  of  five  hours,  eight  persons  will  generally 
have  drawn  250  grammes  or  about  8  ounces  of  saffron  In  some 
places  the  pistils  are  dried  in  the  sun,  in  others  by  being  exposed  in 
a  sieve  over  a  fire  of  twigs ;  the  latter  process  appears  to  be  the 
better  one. 

M.  de  Gasparin  estimates  at  about  110  lbs.  the  saffi-on  which  is 
gathered  in  the  course  of  two  years  from  about  2j\ths  acres  of  land  ; 
this  would  give  a  mean  annual  produce  of  about  43.7  lbs.  per  Eng- 
lish acre,  and  the  price  of  saffron  being  from  27  to  28  shillings  per 
pound,  the  value  of  the  produce  may  easily  be  reckoned.  In  Aus- 
tria, where  the  crop  is  allowed  to  occupy  the  ground  for  three  years, 
the  produce  has  been  estimated  at  about  19^  lbs.  per  acre  per  annum. 

Roucou  is  a  dye-stuff  extracted  from  the  fruit  of  the  Bixa  orel- 
lana,  a  tree  which  is  extremely  common  in  the  hot  regions  of  South- 
ern America. 

Chica.  This  and  the  former  dye-stuff  are  in  use  among  the  na- 
tive Americans  for  staining  the  skin.  It  is  obtained  from  the  leaves 
of  the  Bignonia  chica,  which  are  of  a  beautiful  green  when  fresh, 
but  become  red  by  drying. 

Chica  has  the  color  of  cinnabar :  it  is  without  taste  and  v  ithout 
tmell :  a  mass  of  this  pigment  may  be  compared  to  a  mass  of  indigo 


154  THE  POTATO. 

It  only  differs  from  this  substance  in  its  color.  Like  indigo,  it  ac« 
quires  the  metallic  polish  when  rubbed  with  a  hard  body.  It  dis- 
solves in  alcohol,  and  in  alkaline  solutions  ;  it  mixes  readily  with 
grease,  and  it  is  with  such  a  mixture  that  the  Indians  paint  their 
bodies.  Chica  has  been  employed  in  cotton-dyeing,  and  the  color  is 
found  to  stand  the  sun  perfectly. 


§  XL— COMPOSITION  OF  THE  DIFFERENT  PARTS  OF 
PLANTS 

The  immediate  principles,  the  history  of  which  has  now  been 
sketched,  are  met  with  in  greater  or  lesser  quantities  in  different 
parts  of  plants  ;  some  of  them  are  accumulated  in  the  roots,  others 
in  the  seeds,  the  barks,  the  leaves,  &c.  To  complete  the  study  of 
the  chemical  constitution  of  vegetables  we  have  still  to  examine 
with  reference  to  their  composition  certain  parts  or  organs  which 
present  sufficient  interest  either  from  their  extensive  employment  or 
their  importance  in  an  agricultural  point  of  view. 

ROOTS    AND    TUBERS. 

The  Potato,  {Solarium  tuberosum.)  This  plant  is  a  native  of 
South  America.  Two  English  travellers,  Messrs.  Caldcleugh  and 
Baldwin,  were  so  fortunate  as  to  meet  with  it  lately  in  the  vild  state  in 
Chili,  and  not  far  from  Monte  A^ideo.  It  is  probable  that  the  culti- 
vation of  the  potato  spread  from  the  mountains  of  Chili  to  the  chain 
of  the  Andes,  proceeding  northward  and  obtaining  a  footing  suc- 
cessively in  Peru,  at  Quito,  and  upon  the  plateau  of  New  Granada. 
This,  as  Humboldt  observes,  is  precisely  the  course  which  the  Incas 
took  in  their  conquests.  The  potato  does  not  appear  to  have  been 
introduced  into  Mexico  until  after  the  European  invasion  of  that 
country ;  and  it  is  well  ascertained  that  it  was  not  known  there  un- 
der the  reign  of  Montezuma,  although  there  are  not  wanting  some 
who  maintain  that  the  potato  was  found  in  Virginia  by  the  first  colo- 
nists sent  thither  by  Sir  Walter  Raleigh.  It  is  said  that  it  was  then 
brought  into  England  by  Drake  ;  but  it  seems  well  established  that 
long  before  Drake's  time,  namely,  in  1545,  a  slave  merchant,  John 
Hawkins  by  name,  had  introduced  tubers  of  the  potato  from  the 
soasts  of  New  Granada  into  Ireland.  From  Ireland  the  new  plant 
passed  into  Belgium  in  1590.  Its  cultivation  was  at  this  time  neg- 
lected in  Great  Britain,  until  it  was  introduced  by  Raleigh  at  the 
beginning  of  the  seventeenth  century.  When  the  potato  came  from 
Virginia  to  England  for  the  second  time  it  was  already  disseminated 
over  Spain  and  Italy.  It  has  been  ascertained  that  the  potato  has 
been  cultivated  on  the  great  scale  in  Lancashire  since  1684  ;  in 
Saxony  since  1717 ;  in  Scotland  since  1728  ;  in  Prussia  since  1738,* 

*  Humboldt,  Essai  PoUtiqoo,  t.  ii.  p.  46JI. 


THE   POTATO.  155 

IV  «ras  about  the  year  1710  that  the  potato  began  to  spiead  in  Ger- 
many, and  that  it  there  became  a  plant  in  common  use  ;  it  had,  in- 
deed, before  this  time  been  cuhivated  in  gardens ;  and  had  even 
made  its  appearance  at  the  tables  of  the  rich  some  time  previously. 
The  severe  dearth  of  the  years  1771  and  1772*  seemed  necessary 
to  lead  the  Germans  to  cultivate  this  useful  plant  upon  the  great 
scale.  From  this  time  it  was  shown  that  it  was  a  substitute  for 
bread  ;  and  once  fairly  introduced,  men  were  not  long  of  perceiving 
the  many  recommendations  which  it  possesses  as  an  article  of  food. 
In  fact,  of  all  the  useful  plants  which  the  migrations  of  communi- 
ties and  distant  voyages  have  brought  to  light,  says  M.  Humboldt, 
there  is  none  since  the  discovery  of  the  cereals,  that  is  to  say,  from 
time  immemorial,  which  has  had  so  decided  an  influence  upon  the 
well-being  of  mankind.  In  less  than  two  centuries  it  may  be  said 
literally  to  have  overspread  the  earth,  or  to  have  been  welcomed  in 
every  country  suited  to  its  cultivation,  so  that  at  the  present  day  it  is 
found  growing  from  the  Cape  of  Good  Hope  to  Iceland  and  Lap- 
land. "  It  is  an  interesting  spectacle,"  adds  the  illustrious  traveller 
quoted,  "  to  see  a  plant,  a  native  of  mountains  situated  under  the 
equator,  advance  towards  the  pole,  and  growing  even  more  hardily 
than  the  grasses  which  yield  ns  grain,  brave  the  inclemencies  of  the 
North, "I  The  potato,  like  all  other  tubers,  is  a  collection,  an  exu- 
berance which  is  evolved  upon  the  subterraneous  stems.  Its  varie- 
ties, which  are  very  numerous,  present  rather  remarkable  differences 
in  regard  to  size,  form,  color  of  the  surface  and  of  the  interior,  taste, 
and  the  time  which  they  require  to  come  to  maturity. 

Next  to  water,  fecula  or  starch  is  the  principle  which  predominates 
in  the  potato,  but  it  also  contains  a  certain  quantity  of  azotized  mat- 
ter. Vauquelin  has  published  a  detailed  account  of  the  soluble  mat- 
ters which  are  met  with  in  the  potato,  and  which,  strange  to  say, 
have  been  neglected  in  the  greater  number  of  analyses  of  this  useful 
vegetable  which  have  been  published.  In  100  parts  of  potatoes  he 
found  :  asparagine  0.1,  albumen  0.7,  azotized  matter  not  defined  0.4, 
citrate  of  lime  1.2,  and  undetermined  quantities  of  citrate  of  potash, 
free  acetic  acid,  phosphate  of  potash,  and  phosphate  of  lime. 

In  examining  forty-eight  varieties  of  potato  he  found  that  they 
contained  in  100  parts  :  first,  from  1  to  U  of  pulp  ;  second,  from  2 
to  3  of  soluble  or  extractive  substances ;  third,  from  20  to  28  of 
starch ;  fourth,  from  67  to  78  of  water.| 

In  a  variety  grown  in  the  neighborhood  of  Paris,  Henry  found  the 
following  ingredients,  viz  :  pulp  6.8,  starch  13.3,  albumen  0.9,  un- 
crystallizable  sugar  3.3,  acids  and  salts  1.4,  fatty  matter  0.1,  and 
water  74.2=100.0. 

The  proportion  of  starch  varies  considerably  in  the  diflferent  va- 
rieties ;  M.  Payen  has  ascertained  the  extent  of  this  diversity  in  a 
certain  number  of  varieties  grown  in  the  same  soil  and  under  the 

*  Thaer,  Principes  raisonn6s  d'Agriculture  I.  iv.  p  lift, 

i  Humboldt,  op.  cit.  t.  ii.  p.  463. 
TWnard'a  Chemistry,  vol.  v.  p.  82. 


156 


THE    POTATO. 


same  circumstances. 

table : 


The  results  are  contained  in  the  foJowins 


VarieUes. 

One  of 

seed 
potatoes 
pro- 
duced. 

Produce  per  Acre. 

In  100  parU. 

Starch. 

I 
Starch  per  Acre. 

Dry 
matter. 

Water. 

The  Rohan 

The  great  yellow  . 
The  Scotch  shaws 
The  late  Iceland-. 

TheSegonzac 

The  Siberian 

TheDuvillers 

58 
37 
32 
56 
32 
40 
40 

tons.  cwts.  qrs.  lbs.! 

14    14      2    16    24.8 
9      8      0    271  31.3 
8      3      2      2    30.2 

14      6      1    23    20.6 
8      3      2      2    28.8 

10      4      2    12    22.2 

10      4      2    12    21.7 

75.2 
68.7 
69.8 
79.4 
71.2 
77.8 
78.3 

1G.6 
23.3 
22.0 
12.3 
20.5 
14.0 
13.6 

tons.  cwt.  qrs.  lbs. 
2      9    0    12 
2      3    3      4 
1    16    0      1 
1    15    1      2 
1    14    0      5 
1      8    2    16 
1      8    0    12 

In  the  particular  circumstances  under  which  this  experiment  wa? 
made,  therefore,  it  is  obvious  that  the  Rohan  variety  contained  the 
larjrest  quantity  of  nutritive  matter  and  starch. 

Potatoes  which  have  been  exposed  to  a  temperature  a  few  degrees 
below  the  freezing  point  of  water,  undergo  so  great  a  change  in  their 
texture,  that  it  becomes  difficult  afterwards  to  extract  the  starch 
which  they  contain.  They  besides  acquire  so  disagreeable  a  flavor, 
as  all  the  world  knows,  that  cattle  sometimes  refuse  to  eat  them. 
After  having  ascertained  that  a  potato  has  the  same  chemical  com- 
position before  and  after  congelation,  M.  Payen  examined  the  starchy 
substance  under  the  microscope,  and  found  that  the  starch  obtained 
from  a  frozen  tuber  presented  itself  in  compound  granular  masses, 
four  or  five  times  the  size  of  the  largest  natural  grains  of  starch. 
The  pulp  which  remained  upon  the  sieve  in  the  preparation  of  this 
starch,  was  formed  by  a  collection  of  cells,  for  the  most  part  full  of 
starch.  It  would  therefore  appear,  that  in  consequence  of  the 
changes  of  volume  of  the  fluid  successively  congealed  and  liquefied, 
the  adhesion  between  the  cells  was  destroyed  :  they  become  separa- 
ble with  the  slightest  force,  and  merely  part  one  from  another  by 
the  action  of  the  grater  without  being  torn ;  the  larger  number  re- 
main unbroken  and  still  filled  with  starch.  This  fact  enables  us  to 
understand  how  potatoes,  which  have  been  frozen,  will  yield  nearly 
the  whole  of  their  starch  if  they  be  treated  before  they  are  thawed. 
The  cells  then  sealed  up  by  the  congealed  water  resist  sufficiently 
to  be  broken  by  the  teeth  of  the  grater.  Potatoes  which  have  been 
i'rozen,  are  generally  less  farinaceous,  at  the  same  time  that  they  have 
a  decidedly  sweet  taste,  which,  according  to  M.  Payen,  is  owing  to 
vegetation  having  already  made  some  progress  in  the  tubers  before 
congelation ;  and  we  know  that  during  germination  there  is  always 
a  formation  of  sugar  at  the  expense  of  the  fecula.  Frosted  potatoes 
have  always  a  disagreeable  taste,  and  a  most  unpleasant  smell,  so 
that  in  many  places  they  are  thrown  upon  the  dunghill.  The  effect 
of  the  frost,  in  fact,  is  to  set  the  juices  which  are  enclosed  in  the 
tissue  of  the  potato  at  liberty,  and  the  higher  temperature  which  ac- 
Isoinpanies  and  follows  i  thaw  ,  exposes  these  juices  to  be  acted  upon 


THE    POTATO.  157 

immediately  by  the  air  of  the  atmosphere,  the  consequence  of  which 
is,  that  they  behave  like  all  other  vegetable  juices  left  to  themselves, 
they  become  putrid.  The  putrid  odor  and  the  acrimony  which  are 
developed  in  the  frosted  potato,  are  by  so  much  the  more  remarkable 
as  a  certain  layer  which  exists  immediately  under  the  skin,  and  pre- 
sents various  shades  of  color,  tawny  red  or  violet,  is  more  highly 
develo})ed.  The  tissue  of  this  layer,  examined  under  the  micro- 
scope, was  found  by  M.  Payen  to  be  totally  without  starch,  but  it 
contains  the  greater  part  of  the  (strong-smelling)  coloring  principles.* 
These  principles,  which  give  such  unpleasant  qualities  to  frosted 
potatoes,  appear  to  be  soluble,  or  at  least  destructible  by  long  expo- 
sure to  the  open  air.  Thus,  if  frosted  potatoes  be  spread  upon  the 
ground  and  exposed  to  the  weather,  they  dry  spontaneously,  become 
hard,  whitened,  and  they  may  then  be  preserved  for  a  very  long 
time.  This  method  of  making  use  of  frosted  potatoes  Jias  been 
several  times  employed  in  practice,  and  it  might  perhaps  be  recom- 
mended for  general  adoption,  were  it  only  ascertained  that  by  such 
treatment  the  tubers  did  not  lose  a  great  proportion  of  their  most 
nutritive  principle,  viz.  albumen.  However  this  may  be,  it  is  by  a 
similar  process  that  the  natives  of  the  Andes  of  Peru  preserve  and 
render  more  transportable  the  tubers  which  form  a  principal  element 
in  their  food.  In  the  steepest  parts  of  the  Peruvian  Cordillera, 
nearly  at  the  superior  limit  of  vegetation,  where  a  miserable  field  of 
barley  and  of  Quinoa  is  only  seen  here  and  there,  various  tubers  are 
collected  in  the  hollows  of  the  surface,  such  as  the  Maca^  the  Oca^ 
the  Ulluco.  To  preserve  these  they  are  exposed  for  several  days  to 
the  alternate  action  of  the  frost  and  of  the  sun.  At  these  great 
elevations,  which  are  upwards, of  13,120  feet  above  the  level  of  the 
sea,  it  always  freezes  in  clear  nights  when  the  air  is  moderately 
calm.  During  the  day  the  rays  of  the  sun,  which  strike  with  great 
force,  dry  the  tubers  rapidly,  the  watery  juices  of  which  have  been 
shed  into  the  amylaceous  tissue  by  the  effect  of  the  preceding  night's 
frost.  Thoroughly  dry,  they  may  be  kept  for  more  than  a  year  by 
being  stored  and  protected  from  moisture.  Various  other  modes  of 
preparation  are  practised  in  regard  to  the  other  kinds  of  tubers  which 
have  been  mentioned.  By  previously  boiling  the  common  potato, 
pealing  it,  and  exposing  it  alternately  to  the  frost  of  the  night  and 
the  heat  of  the  sun,  until  it  is  completely  dry,  the  Indians  prepare 
one  of  their  most  agreeable  and  wholesome  articles  of  subsistence. 
The  potato  thrives  in  soils  of  very  various  kinds,  provided  it  be 
sufficiently  fertile,  and  the  climate  is  favorable.  This  crop,  like  the 
beet,  is  generally  planted  in  freshly  manured  ground,  and  is  suc- 
ceeded in  the  autumn  by  a  winter  crop  of  corn — wheat  or  rye.  The 
potato  is  set  when  apprehensions  of  frost  are  no  longer  entertained  .. 
in  the  east  of  France  the  setting  is  generally  ended  about  the  mid- 
dle of  May.  In  Alsace  the  cuttings  of  the  potato  are  dropped  at 
the  distancB  of  about  a  foot  from  each  other  in  furrows  made  by  the 
plough,  the  furrows  being  from   18  inches  to  nearly  2  feet  apart* 

*  Payen.  Journril  of  Practical  Agriculture,  vol.  i.  p.  4S8, 

14 


158  THE    POTATO. 

When  tlie  plants  are  from  10  to  12  inches  high,  and  the  weather  i« 
dry,  the  furrows  are  lightly  earthed  up.  In  dry  soils  the  earthing 
plough  must  not  be  carried  very  deeply  ;  and  I  may  say  that  in  the 
elevated  table  lands  of  America,  where  the  natural  drought  of  the 
climate  is  often  to  be  apprehended,  I  have  seen  very  fine  crops  of 
potatoes  which  had  never  been  earthed  up  at  all.  The  potato,  like 
all  plants  that  are  hoed,  requires  considerable  care  ;  but  this  care, 
as  it  is  immediately  profitable,  is  still  more  so  remotely  upon  the 
white  crops  which  are  to  follow.  M.  Crud  reckons  at  58.3  the 
number  of  days  work  that  are  required  upon  an  acre  of  land  which 
has  received  between  19  and  20  tons  of  manure.  This  is  very 
nearly  what  we  have  found  to  be  the  truth  at  Bechelbronn,  where  for 
the  same  extent  of  surface,  manured  in  the  same  way,  we  reckon 
fifty  days  labor  of  a  man,  and  rather  better  than  eleven  davs  of  a 
horse. 

In  Europe  the  potato  harvest  takes  place  at  the  end  of  autumn. 
In  the  intertropical  Cordillera,  where  the  cultivation  depends  prin- 
cipally upon  the  heat  of  a  very  steady  climate,  the  potato  remains 
in  the  ground  from  four  to  seven  months,  as  it  is  cultivated  at  a 
greater  or  less  height  above  the  level  of  the  sea  ;  it  succeeds  be=« 
where  the  mean  temperature  ranges  between  13°  and  18°  centigrade, 
(56°  and  65°  Fahr.)  In  Venezuela,  indeed,  it  is  still  cultivated  in 
places  where  the  temperature  is  not  far  from  24°  centigrade,  (76.5° 
Fahr.;)  but  I  am  doubtful  that  the  culture  is  then  advantageous.  In 
warm  and  moist  regions  the  potato  yields  a  large  quantity  of  top, 
and  few  tubers.  I  have  gathered  some  very  bad  ones  at  Riosflcio 
de  Engurama,  a  village  situate  at  the  distance  of  about  5900  feet 
above  the  level  of  the  sea,  where  the  mean  and  constant  tempera- 
ture is  about  22°  centigrade,  (72°  Fahr.) 

The  produce  per  acre,  noted  by  different  observers,  is  as  follows : 


Countries. 

Tons. 

Cwts. 

Ors. 

lbs. 

Prussia  .... 

. 

5 

18 

2 

1 

Palatinate,  mean  of  ten  years 

5 

7 

1 

14 

Austria,  mean  of  thirteen 

years 

9 

11 

3 

10 

Brabant 

11 

17 

0 

2 

West  Flanders 

9 

13 

0 

17 

Pays  de  Waes 

10 

8 

3 

13 

Pays  de  Tongres     . 

6 

14 

0 

25 

England 

10 

2 

2 

7 

England 

9 

9 

0 

25 

Ireland 

9 

9 

3 

14 

Alsace 

8 

14 

3 

8 

Alsace  (Bechelbronn)     . 

5 

8 

1 

12 

Neighborhood  of  Paris    . 

11 

2 

2 

13 

Venezuela 

9 

16 

1 

20* 

There  is  an  obvious  relation  between  the  quantity  of  seed-potato 
planted  and  the  amount  of  the  crop.  In  Alsace  from  25  to  30 
buehels  per  acre  are  usually  planted.     In  some  places  too  much  seed 

•  This  is  the  produce  of  two  harvests,  which  they  gather  In  the  same  year. 


JERUSALEM    ARTICHOKE.  159 

is  used,  in  others  not  enough.  It  were  very  desirable  thai  certain 
experiments  were  undertaken  which  should  fix  the  pre  per  quantity 
of  seed-potato  to  be  used  for  each  variety  of  soil  and  situation. 

The  Jerusalem  Artichoke,  {Helianthus  tuherosus.)  This  plant  is 
generally  believed  to  be  a  native  of  South  America,  but  M.  de  Hum- 
boldt never  met  with  it  there,  and  according  to  M.  Correa,  it  does 
not  exist  in  Brazil.  The  property  which  the  tubers  of  this  plant 
have  of  resisting  the  cold  of  our  winters,  and  several  botanico-geo- 
a^raphical  considerations,  lead  M.  A.  Brongniart  to  presume  that  the 
plant  belongs  to  the  more  northern  parts  of  Mexico. 

The  Jerusalem  artichoke  rises  to  a  height  of  from  9  to  10  feet; 
it  flowers  late,  and  I  have  not  yet  seen  it  ripen  its  seeds.  It  is  pro- 
pagated by  the  tubers  which  it  produces,  and  which  are  regarded^ 
for  good  reason,  as  most  excellent  food  for  cattle ;  in  times  when 
the  potato  was  not  very  extensively  known,  it  also  entered  pretty 
largdy  into  the  food  of  man  ;  when  boiled,  its  taste  brings  to  mind 
that  of  the  artichoke,  whence  the  name. 

The  tuber  of  the  Jerusalem  artichoke,  from  an  analysis  of  M. 
Braconnot,  appears  to  contain  in  100  parts : 

Uncrystallizable  sugar  .  .         .       14.80 

Inuliue 3.00 

Gum 1.22 

Albumen 0.99 

Fatty  matter 0.09 

Citrates  of  potash  and  lime  .         ....         1.15 
Phosphates  of  potash  and  lime     .  0.20 

Sulphate  of  potash        .         .         .  0.12 

Chloride  of  potassium 0.08 

Malates  and  tartrates  of  potash  and  lime     .         .         0.05 

Woody  fibre 1.22 

Silica 0.03 

Water 77.05 

100.00 
M.  Payen  found  a  larger  proportion  of  sugar  in  this  tuber  than  that 
stated  above,  and  he  ascertained  that  the  fatty  matter  consists  chiefly 
of  stearine  and  elaine.     In  the  Jerusalem  artichoke  I  myself  found  : 

Of  dry  matter 20.8 

Water ■-    79.2 

lOO.d 

One  trial  for  azote  would  lead  me  to  conclude  that  M.  Braconnct 
had  estimated  the  albumen  too  low  in  his  analysis,  or,  as  is  more 
probable,  that  several  azotized  principles  had  escaped  him.  The 
dried  tuber  gave  me  0.16  of  azote,  a  number  which  would  indicate 
1.0  as  the  proportion  of  vegetable  albumen.  There  are  few  plants 
more  hardy  and  so  little  nice  about  soil  as  the  Jerusalem  artichoke ; 
it  succeeds  everywhere,  with  the  single  condition  that  the  ground  be 
not  wet.  The  tubers  are  planted  exactly  like  those  of  the  potato, 
and  nearly  at  the  same  time  ;  but  this  is  a  process  that  is  performed 
but  rarely,  inasmuch  as  the  cultivation  of  the  helianthus  is  incessant, 


160  JERUSALEM    ARTICHOKE. 

being  carried  on  for  many  years  in  the  same  piece ;  and  after  th© 
harvest,  in  spite  of  every  disposition  to  take  up  all  the  tubers, 
enough  constantly  escape  detection  to  stock  the  land  for  the  follow- 
ing year,  so  that  the  surface  appears  literally  covered  with  the  young 
plants  on  the  return  of  spring,  and  it  is  necessary  to  thin  them  b}r 
hoeing.  The  impossibility  of  taking  away  the  whole  of  the  tubers, 
and  their  power  of  resisting  the  hardest  frosts  of  winter,  is  an  ob- 
stacle almost  insurmountable  to  the  introduction  of  this  plant,  as  one 
element  in  a  regular  rotation.  Experience  more  and  more  confirms 
the  propriety  of  setting  aside  a  patch  of  land  for  the  growth  of  this 
productive  and  very  valuable  vegetable  root. 

Of  all  the  plants  that  engage  the  husbandman,  the  Jerusalem 
artichoke  is  that  which  produces  the  most  at  the  least  expense  of 
manure  and  c«f  manual  labor.  Kade  states  that  a  square  patch  of 
Jerusalem  artichokes  in  a  garden  was  still  in  full  productive  vigor 
at  the  end  of  thirty-three  years,  throwing  out  stems  from  7  to  10 
feet  in  length,  although  for  a  very  long  time  the  plant  had  neither 
received  any  care  nor  any  manure.* 

I  could  quote  many  examples  of  the  great  reproductive  power  of 
the  helianthus  ;  I  can  affirm,  nevertheless,  that  in  order  to  obtain 
abundant  crops,  it  is  necessary  to  afford  a  little  manure.  I  shall 
show  in  another  chapter,  however,  that  this  is  manure  well  bestowed. 

Like  all  vegetables  having  numerous  and  large  leaves,  the  helian- 
thus requires  air  and  light ;  it  ought,  therefore,  to  be  properly  spaced 
The  original  planting  of  course  takes  place  in  lines,  but  in  the  suc- 
ceeding crops,  and  those  which  are  derived  from  small  tubers  acci- 
dentally left  in  the  ground,  the  order  is  of  course  lost ;  it  is  only 
necessary  to  destroy  a  sufficient  number  of  the  young  sprouts  which 
show  themselves  in  the  spring,  to  leave  those  plants  that  are  pre- 
served with  a  sufficient  space  between  them.  When  the  plants  are 
somewhat  advanced,  the  ground  should  receive  one  or  two  diggings 
with  the  spade,  and  a  hoeing  or  two  to  destroy  weeds. 

The  leaves  of  the  helianthus  are  used  in  many  places  as  forage, 
the  stems  being  cut  a  few  inches  from  the  ground  ;  the  gathering 
takes  place  at  different  periods  of  the  year,  but  probably  to  the  detri 
ment  of  the  tubers ;  it  may  be  lucrative  to  destine  the  leaves  for  l\v 
nutriment  of  cattle,  but  I  believe  we  have  to  choose  between  th' 
green  crop  and  the  crop  of  tubers.     It  is  unquestionable  that  tht 
premature  removal  of  the  green  stems  must  prove  injurious  to  thft 
roots ;  in  my  own  farm  the  leaves  are  never  removed,  and  my  opir 
ion  is,  that  it  is  vastly  more  advantageous  to  depend  upon  the  crop 
of  tubers  alone.     The  tubers  are  gathered  as  they  are  wanted,  fo. , 
not  dreading  the  frost,  they  remain  in  the  ground  the  whole  of  th** 
winter ;  they  do  not  require,  like  the  potato,  to  be  collected  and  pit- 
ted at  a  certain  period  ;  they  require  no  particular  situation,  no  par 
ticular  care  for  their  preservation ;  the  only  disadvantage  that  ac 
companies  their  being  left  in  the  ground,  is  that  during  very  hard 
frosts  the  labor  required  to  get  at  them  is  very  great.     During  win 

•  Schwertz  Cultnrc  of  Fonee  Plants. 


THE    CARROT.  161 

ter  the  woody  stsms  of  the  plant  die  and  dry  up,  tliey  are  then  use- 
ful as  combustible  matter ;  but  a  better  use  of  them  perhaps  is  to 
make  them  enter  in  certain  proportions  into  the  litter  of  the  hog- 
stye  ;  the  pith  there  absorbs  a  large  quantity  of  the  liquid  manure. 
Schwertz  estimates  the  mean  quantity  of  dry  leaves  and  stems  at  3 
tons,  1  cvvt.  1  qr.  and  15  lbs.  per  acre.  The  following  quantities 
of  tubers  have  actually  been  gathered  in  Alsace. 

Tons.  Cwts.  Qjs.  lbs. 

Sandysoils 4  3  3  6 

Soils  of  the  best  quality 10  8  3  13 

At  Bechelbronn  Cmean) 10  16  0  8 

Bechelbronn  crops  of  1839-40 15  16  1  16 

The  Carrot,  {Daucus  carota.)  This  root  is  frequently  cultivated, 
particularly  by  intercalation  ;  it  is  frequently  grown  along  with  the 
poppy,  where  the  seed  is  raised  for  the  sake  of  its  oil,  occasionally  also 
being  sown  with  white  crops  in  the  spring,  it  comes  to  maturity  after 
them  in  the  autumn  ;  it  is  a  plant  that  is  much  liked  by  animals,  but 
which  by  no  means  possesses  the  very  high  value  as  an  article  of  food 
which  is  generally  ascribed  to  it  by  husbandmen.  The  carrot  requires 
a  deep,  somewhat  loose  and  homogeneous  soil,  fresh  manure,  and 
much  care  in  the  cultivation.  Schwertz,  taking  the  mean  of  three 
years,  estimates  the  produce  per  acre  at  13  tons,  18  cwt.  1  qr.  and 
2  lbs.  of  roots,  and  about  one-third  the  same  quantity  of  green  leaves, 
which  are  valuable  as  fodder  and  as  elements  of  manure.  In  a  field 
at  Bechelbronn  where  this  vegetable  had  been  intercalated  with  the 
madia  sativa,  we  obtained  upwards  of  5|  tons  of  roots  in  addition  to 
our  principal  crop  of  oleaginous  seed.  The  carrot  contains  a  large 
quantity  of  water  in  its  constitution — 87.6  percent.,  according  to 
some  of  my  experiments. 

The  juice  of  the  carrot  contains  sugar,  albumen,  a  erystallizable 
coloring  principle,  called  carrotine,  a  volatile  oil,  fatty  matters,  pectic 
acid,  pectine,  starch,  malic  acid  and  alkaline,  and  earthy  phosphates. 

The  parsnip,  {Pastinaca  sativa.)  This  plant  is  not  very  exten- 
sively cultivated,  yet  it  has  the  advantage  of  standing  the  winter  in 
the  open  field.  It  has  been  recommended  as  very  useful  in  fattening 
cattle.  In  its  composition  it  must  assimilate  with  the  carrot  and 
beet.  Drappier  obtained  as  much  as  12  per  cent,  of  cane-sugar 
from  the  parsnip.* 

BARKS. 

Cinchona  barks.  The  barks  of  cinchona,  which  are  employed 
with  so  much  success  in  medicine,  are  the  produce  of  different  species 
of  a  family  of  trees  which  grows  in  the  mountains  of  South  Ameri- 
ca ;  the  active  principle  of  all  the  varieties  of  bark  resides  in  the 
vegetable  alkalies,  quinine,  cinchonine,  and  cinchovatine. 

The  medicinal  properties  of  bark  were  made  known  to  Europeans 
in  1638,  on  the  occasion  of  an  obstinate  fever  from  which  the  Coun- 
tess of  Chincon,  vice-queen  of  Peru,  suffered  at  Lima  in  that  year. 
A  corregidore  of  Loxa,  who  had  been  cured  by  the  Indians  while 

*  Berzelius-,  Chemistry,  vol.  ii.  p.  199. 
14* 


162  CINCHONA  BARKS. 

affected  in  the  same  way,  recommended  the  bark.  The  medicine 
was  completely  successful ;  and  to  show  her  gratitude,  the  vice- 
queen  had  large  quantities  brought  down  from  the  mountains  for 
distribution  among  persons  affected  with  fever.  It  was  from  this 
circumstance  that  the  bark  was  at  first  known  under  the  name  of 
the  Countess's  powder.  By  and  by,  the  members  of  the  college  of 
Jesuits  having  been  charged  with  its  distribution,  it  of  course  be- 
came the  Jesuits'  bark  or  powder.  Lastly,  the  Cardinal  de  Lugo 
having  brought  it  to  Rome,  the  new  medicine  was  known  under  the 
name  of  the  cardinal's  powder. 

The  cinchonas  are  met  with  principally  in  forests  at  a  considerable 
elevation  above  the  level  of  the  sea,  in  a  temperate  climate,  and 
growing  in  a  stony  soil.  The  proper  period  for  gathering  is  known 
by  the  circumstance  of  the  inner  surface  of  the  bark,  when  detached 
from  a  branch,  acquiring  in  a  few  minutes  a  red,  yellow,  or  orange 
tint,  according  to  the  species. 

The  trees  are  cut  down  one  or  two  days  before  the  process  of 
barking  begins,  by  which  the  operation  is  rendered  more  easy,  and 
the  cuticle  is  no  longer  liable  to  be  rubbed  off.  The  bark  of  the 
trunk  and  branches  is  removed  by  means  of  a  large  knife,  in  strips, 
or  bands,  which  are  kept  as  broad  as  possible.  I'he  bark  is  placed 
upon  cloths  and  put  to  dry  in  the  sun,  each  piece  being  kept  isolated, 
in  order  to  facilitate  the  drying,  and  especially  to  favor  the  quilling 
or  rolling  up ;  when  the  bark  is  dried  in  a  heap,  and  when  the  pieces 
touch,  it  often  acquires  a  most  disagreeable  odor  in  consequence  of 
incipient  putrefaction,  and  the  quilling  does  not  take  place.*  The 
bark,  when  thoroughly  dry,  is  packed  in  bullocks'  hides  and  sent  to 
Europe.  From  my  own  observations,  and  those  that  have  been 
supplied  me  by  M.  Goulot,  the  different  species  of  bark  appear  to  be 
distributed  upon  the  mountains  of  New  Granada  in  the  following 
order : 

Hei°^hts  where 
mosl  abundant.       Temperature. 

Gray  bark,  C.  lancifolia 6560  feet  19  "  (66i  F.) 

White  bark,  C.  ovalifolia 4264    "  21"  (70    F.) 

Red  bark,  C.  oblongifolia 2296    "  24  °  (75i  F.) 

Yellow  bark,  C.  cordifolia 1968    "  25°  (77    F.) 

Pelletier  and  Caventou  discovered  in  the  gray  bark,  1st,  cincho- 
nine  in  combination  with  quinic  acid  ;  2d,  a  fatty  substance  ;  3d,  red 
and  yellow  coloring  matters;  4th,  tannin  ;  5th,  quinate  of  lime  :  6th, 
gum  ;  7th,  starch  ;  8th,  woody  matter.  In  the  yellow  and  red  bark 
these  learned  chemists  found  the  same  principles,  and,  moreover, 
quinate  of  quinine. 

Barks  of  the  willow  and  poplar.  Decoctions  of  these  barks  are 
often  employed  with  success  in  the  treatment  of  intermittent  fever. 
In  searching  after  the  active  principle  of  these  medicines,  M.  Roux 
discovered  the  particular  substance,  salicine,  in  the  bark  of  the  wil- 
low, (salix  helix,)  the  medicinal  effect  of  which  is  analogous  with 
*hat  of  the  febriluge  principles  of  the  true  barks.     M.  Braconnot  has 

*  Ruiz,  Quinologia. 


CORK.  163 

further  succeeded  in  obtaining  another  crystalline  m%tter  from  the 
leaves  of  the  aspen  (populus  tremula)  populine. 

Cork.  The  oak  which  yields  cork  is  known  in  Spain  under  the 
name  of  the  alcornoque  It  forms  extensive  forests  upon  the  abrupt 
slopes  of  the  Pyrenees,  where  it  is  often  seen  growing  upon  arid  and 
stony  soils,  that  seem  doomed  to  eternal  sterility.  The  cork-tree 
has  flexible  and  strong  roots,  which  creep  over  the  naked  surface  of 
the  granitic  masses,  turning  round  blocks,  and  searching  everywhere 
for  fissuj-es  and  collections  of  sand  and  alluvium,  into  which  they 
penetrate  deeply,  in  search  of  the  nourishment  necessary  to  the  tree. 
At  maturity,  the  alcornoque  rises  to  a  height  of  sixty-five  feet,  and 
its  trunk  may  be  three  feet  and  a  quarter  in  diameter. 

In  the  Spanish  Pyrenees,  the  superior  limit  of  the  cork-tree  region, 
is  that  of  the  vine,  about  1640  feet  above  the  level  of  the  Mediter- 
ranean. In  France  this  tree  grows  luxuriantly  in  the  communes  of 
Passa,  Lauro,  &c.,  the  mean  elevation  of  which  is  1148  feet.  In 
Spain,  as  in  France,  the  soils  on  which  the  cork  forests  grow  are  of 
primitive  origin  ;  and  it  is  said,  on  good  authority,  that  the  cork- 
tree only  grows  on  soils  derived  from  granite,  gneiss,  mica-slate,  or 
porphyry,  and  never  on  soils  of  calcareous  origin. 

The  cork-tree  is  reproduced  spontaneously  on  these  silicious  soils, 
among  cistuses  and  heaths  ;  but  the  reproduction  in  this  way  is  so 
slow,  that  art  often  interferes  advantageously  to  aid  it.  There  are 
many  varieties  of  cork  oak;  and  as  that  which  is  covered  with  a 
smooth  and  grayish  cuticle,  yields  the  article  which  is  most  prized 
in  commerce,  the  seeds  of  this  variety  ought  to  be  selected  for  sow- 
ing. The  acorns  of  the  cork-oak  are  tumid,  of  considerable  size, 
and  a  sweet  taste  ;  the  acorns  ripen  from  October  to  December,  and 
are  much  employed  as  food  for  hogs.  The  Catalonians  sow  the 
acorns  in  a  cultivated  soil  at  the  same  time  that  they  plant  the  vine, 
and  for  twenty  or  twenty-five  years  the  produce  of  the  vine  compen- 
sates the  outlay  upon  the  young  cork-trees  ;  but  the  produce  of  the 
vine  diminishes  as  the  cork-tree  overshadows  it,  and  finally  there 
comes  a  time  when  the  vines  die  out  completely.  The  cork-tree  is 
of  slow  growth,  and  at  four  years  of  age  it  may  be  from  thirty-six  to 
forty  inches  in  height,  and  requires  incessant  care  until  the  trunk  is 
from  seven  to  ten  feet  high,  at  which  time  it  may  be  about  twenty 
years  of  age  ;  and  its  total  height,  including  its  branches,  may  be 
about  twenty-two  feet. 

The  barking  of  the  cork-tree  begins  about  the  middle  of  July,  and 
may  be  continued  so  long  as  the  sap  is  in  motion.  When  stripped 
oflf,  good  cork  is  formed  of  from  ten  to  twelve  layers,  each  of  which 
indicates  an  annual  deposition.  The  two  outer  layers  constitute  the 
cuticle  ;  the  others  adhere  closely  together,  and  although  of  variable 
thickness  they  present  a  homogeneous  mass.  The  time  for  remov- 
ing the  cork  is  indicated  by  the  interior  acquiring  a  slightly  rosy 
tint,  which  happens  about  the  tenth  year.  The  barking  is  performed 
by  me»ns  of  an  axe,  with  which  a  cut  is  made  the  whole  length  of 
the  t»--mk,  care  being  taken  not  to  wound  the  woody  layers :  two 
otJ**'  ':ross  cuts  are  then  made  at  the  top  and  bottom  of  the  trunk. 


164  TOBACCO. 

By  moans  of  the  handle  of  the  axe,  which  is  shaped  like  a  wedje 
forced  into  the  vertical  cut,  the  cork  is  then  loosened  and  stripped 
from  the  livinfrhark  beneath  it,  the  whole  covering  of  the  tree  beinc 
often  taken  away  in  a  single  piece,  although  it  is  more  commonly  re- 
moved in  two  pieces.  The  process  of  barking  is  very  easy  when 
the  sap  is  abundant. 

The  cork-tree  must  be  about  forty  years  of  age  before  its  bark  has 
any  commercial  value ;  that  of  a  tree  of  twenty  years  is  always 
treated  as  rubbish.  An  oak  a  century  old  may  furnish  200  lbs.  of 
marketable  cork ;  as  many  as  480  lbs.  however  have  been  taken 
from  a  single  tree ;  the  mean  produce  may  be  reckoned  at  about  106 
lbs.  per  tree  ;  to  fit  it  for  the  market,  cork  undergoes  a  variety  of 
preparations  which  need  not  detain  us  here. 

LEAVES. 

The  herbaceous  parts  of  vegetables  have  all  a  very  similar  com- 
position, if  they  be  regarded  in  the  most  general  point  of  view.  The 
leaves  and  green  stems,  along  with  the  woody  fibre  which  forms  in 
some  sort  their  skeleton,  always  contain  albumen  or  an  analogous 
azotized  principle,  saccharine  and  gummy  substances,  chlorophylle, 
wax,  fatty  and  resinous  substances,  free  or  combined  acids,  and  fre- 
quently also  essential  oils.  Such  is  the  general  constitution  which 
chemists  agree  in  assigning  to  clover,  hay,  leaves,  in  a  word  to  green 
forage  of  all  kinds  ;  nevertheless,  to  this  constitution,  which  may  be 
regarded  as  standard,  we  have  frequently  other  particular  matters 
added,  some  of  which  we  have  already  studied,  and  which  by  their 
medicinal  properties,  or  the  economic  uses  they  possess,  render  the 
plants  that  contain  them  of  high  importance  in  an  agricultural  point 
of  view.  I  shall  here  only  speak  of  two  of  these  plants,  tobacco 
and  tea,  the  leaves  of  which,  almost  in  universal  use,  are  a  source 
of  great  commercial  prosperity  to  the  people  who  cultivate  them. 

Tobacco,  {Nicotiana  iabacum,)  a  native  of  America,  appears  to 
have  been  introduced  into  Spain  and  Portugal  about  the  middle  of 
the  sixteenth  century  by  Fernandez  de  Toledo.  Its  name  is  gen- 
erally believed  to  be  derived  from  that  of  the  Island  of  Tobago,  one 
of  the  West  India  islands,  at  no  very  great  distance  from  the  coast 
of  Venezuela,  whence  the  first  importations  were  made.  Nicot,  the 
French  ambassador  to  Portugal,  first  made  its  use  known  in  France, 
whence  the  name  nicotiana.  At  the  present  time,  the  cultivation  of 
tobacco  appears  to  have  spread  almost  over  the  whole  surface  of  the 
globe. 

Tobacco  requires  a  somewhat  friable  soil,  rich  in  humus ;  it  con- 
sequently succeeds  in  lands  just  broken  in.  In  America  the  mode 
of  cultivation  and  of  preparation  are  almost  everywhere  the  same. 

In  Venezuela  the  seed  is  sown  in  a  very  ricli  loam,  and  after  from 
forty  to  fifty  days,  the  young  plants  are  transplanted  in  rows,  distant 
a  little  more  than  three  feet  from  one  another,  the  plants  being  about 
two  feet  apart ;  the  transplanted  plant  is  generally  covered  with  a 
banana  leaf  <br  a  few  days  to  preserve  it  from  the  burninjj  rays  of 


TOBACCO.  165 

tne  sun.  When  the  plant  is  about  eighteen  inches  high,  a  bud  is 
formed  at  the  superior  extremity  ;  this  bud  and  any  others  that  may 
appear  are  removed,  as  well  as  any  sprouts  which  show  themselves 
on  the  stem.  By  this  treatment  the  tobacco  becomes  bushy  and 
thick ;  by  and  by  the  leaves  acquire  a  decidedly  blue  tint,  and  the 
time  of  gathering  is  indicated  by  the  appearance  of  a  slain  of  a  deep- 
blue  color  near  the  pedicle.  The  leaves  do  not  all  ripen  simultane- 
ously, so  that  the  business  of  the  planter,  in  gathering  those  that 
appear  ripe,  is  incessant  for  a  certain  time. 

After  they  are  gathered,  the  leaves  are  carried  under  sheds,  where 
they  are  disposed  two  and  two  upon  hurdles  arranged  for  their  re- 
ception. The  tobacco  soon  becomes  yellow  and  pliant,  and  the  ribs 
of  the  leaves  having  been  removed,  they  are  twisted  into  a  rope 
which  is  coiled  up  into  a  mass  of  the  weight  of  from  sixty  to  eighty 
pounds.  These  coils  are  placed  upon  a  bed  made  with  damaged 
leaves  and  the  ribs  which  have  been  removed.  The  whole  is  cover- 
ed, and  left  to  ferment  during  forty  eight  hours,  a  little  water  being 
supplied  if  the  tobacco  appears  too  dry  ;  during  the  fermentation  the 
temperature  rises,  and  the  process  having  been  carried  sufficiently 
far,  the  coils  are  exposed  separately  to  the  air;  they  are  then  un- 
rolled, and  hung  up  under  sheds  to  dry  comj)letely. 

The  vertical  zone  in  which  the  cultivation  of  tobacco  within  the 
tropics  is  carried  on,  is  extensive  ;  it  reaches  from  the  level  of  the 
sea  to  an  elevation  of  about  5,900  feet  above  it.  The  time  during 
which  the  crop  remains  on  the  ground  varies  according  to  the  mean 
temperature  of  the  place  ;  according  to  M.  Codazzi,*the  leaves  are 
gathered  one  hundred  and  fifty  days  after  the  sowing  in  the  hottest 
regions  of  the  coast  of  Venezuela.  In  more  elevated  situations, 
where  the  thermometer  ranges  from  65°  to  68°  Fahr.,  the  first  leaves 
are  not  fit  to  be  gathered  until  after  about  seven  months  and  a  half 
from  the  sowing. 

In  Ceylon,  tobacco  is  cultivated  almost  precisely  as  in  America. 
There  they  also  prevent  the  plant  rising  in  height,  and  they  limit  the 
number  of  leaves  upon  each  stem  according  to  the  quality  of  the 
tobacco  which  they  desire  to  grow.  By  leaving  the  plant  with  no 
more  than  from  ten  to  twelve  leaves,  the  most  esteemed  quality  is 
obtained  ;  if  eighteen  or  twenty  leaves  be  left,  the  tobacco  is  far 
from  having  the  same  strength.  Lastly,  in  leaving  the  plant  to  itself, 
by  suflfering  the  stem  to  run  up  and  to  flourish,  a  large  crop  is 
obtained,  but  the  produce  is  not  esteemed.  Tiie  leaves  gathered 
from  the  plant  in  this  state  of  maturity  are  often  held  fit  for  con- 
sumption after  being  simply  dried  without  further  preparation.  The 
tobacco  is  then  yellow,  extremely  mild,  and'perfectly  suited  to  the 
immoderate  use  made  of  it  by  the  Cingalese. 

If  the  mode  of  cultivation  enables  the  tobacco-grower  to  obtain  a 
superior  quality  at  the  cost  of  quantity,  it  is  still  indubitable  that 
climate  exercises  the  chief  influence  on  the  quality  of  the  article. 
That  which  is  grown  in  the  temperate  regions  of  the  Andes,  in 
Virginia,  and  in  Europe,  can  in  no  way  be  compared  with  the  tobacco 
of  the   Havana,   of  Varinas    of    Giron,   of  the   valley  of  Cauca 


166  TEA. 

The  cultivation  of  tobacco  has  appeared  to  me  moie  especially  ad 
vantageous  in  localities  where  the  mean  temperature  does  not  fall 
below  75°  Fahr. 

Tobacco  is  decidedly  a  plant  of  a  hot  climate  ;  there  only  does  it 
yield  a  produce  of  the  best  quaHty.  In  Venezuela,  where  its  cultiva- 
tion is  followed  with  great  skill,  and  in  situations  where  the  tempe- 
rature of  the  dimate  keeps  from  77°  to  80"  Fahr.,  about  five  plants 
are  held  necessary  to  produce  1  lb.  of  tobacco  ;  and  as  a  mean,  11 
cwt.  1  qr.  23  lbs.  of  the  prepared  article  are  produced  from  an  acre 
of  unmanured  land. 

In  Alsace,  tobacco  is  sown  about  the  middle  of  March  ;  the  trans- 
planting takes  place  in  the  beginning  of  June,  and  the  harvest  fol- 
lows in  autumn.  The  husbandry  is  very  similar  to  that  which  has 
been  already  described,  each  plant  being  left  with  eight  or  ten  leaves. 
Schwertz  reckons  the  produce  at  about  15  quintals  per  hectare  of 
two  and  a  half  acres,  which  is  equal  to  about  12  cwt.  1  qr.  per  Eng- 
lish acre.  Thaer  estimates  the  produce  in  Prussia  at  11  cwt.  1  qr. 
23  lbs.  per  acre. 

The  consumption  of  tobacco  has  lately  increased  considerably 
throughout  the  whole  of  Europe.  In  France,  government  sold  to- 
bacco in  one  form  or  another  to  the  extent  of  31,1 16,340  lbs.  in  the 
course  of  the  year  1837.  Public  documents  show  that  in  1841  there 
were  in  France  8,158  hectares,  or  20,175  acres  under  tobacco, 
which  yielded  21,261,064  lbs.  of  the  article;  the  difference  between 
the  quantity  produced  and  the  quantity  consumed  is  of  course  sup- 
plied by  importation. 

The  virtues  of  tobacco  very  probably  reside  in  the  volatile  vege- 
table alkali,  nicotine,  which  it  contains.  The  analyses  of  M.  Pos- 
selt  and  Kiemann  show  the  leaf  of  tobacco  to  be  composed  as  follows : 
Nicotine  0.07,  extractive  matter  2.87,  gum  1.74,  a  green  resin  0.27, 
albumen  0.26,  gluten  1.05,  malic  acid  0.51,malate  of  ammonia  0.12, 
sulphate  of  potash  0.05,  chloride  of  potassium  0.06,  nitrate  and  ma- 
late  of  potash  0.21,  phosphate  of  lime  0.17,  malate  of  lime  0.73, 
silica  0.09,  woody  matter  4.97,  and  water  86.84, — 100.00.  During 
the  fermentation  of  the  leaves,  there  is  always  a  formation  of  am- 
moniacal  salts. 

Te%  the  use  of  which  is  and  has  so  long  been  universal  in  the 
Chinese  empire,  began  to  be  known  in  Europe  in  the  seventeenth 
century,  when  it  was  imported  by  the  Dutch  East  India  Company. 
In  1669,  the  importation  of  tea  into  England  did  not  exceed  1  cwt.  ; 
in  1833,  the  East  India  Company  set  aside  for  the  consumption  of 
Great  Britain  alone  nearly  24,200,000  of  pounds  ! 

The  tea  plant  commonly  attains  a  height  of  from  three  to  about 
five  feet.  In  China  it  blossoms  in  the  early  part  of  the  spring,  and 
ripens  its  seeds  in  December  and  January,  Its  branches  are  cover- 
ad  with  short  thick  leaves  of  a  deep-green  color  and  elliptical  form. 
it  is  one  of  the  most  hardy  plants,  and  thrives  from  the  equator  to 
the  forty-fifth  parallel  of  north  latitude  ;  but  the  districts  best  adapt- 
ed to  its  growth  appear  to  be  comprised  between  the  twenty-fifth 


TEA.  167 

and  thirty-third  decrees  of  latitude.*  Tea  requires  a  moist  ilimate 
and  a  light  and  sandy  soil.  No  manure  is  given,  and  no  attention 
is  paid  to  the  nature  of  the  soil  where  irrigation  is  practicable. 

The  shrub  is  propagated  from  seed.  Several  seeds  are  dropped 
into  holes  at  the  distance  of  from  three  to  six  feet  apart,  and  the 
plant  begins  to  produce  from  the  third  year  :  the  gathering  is  done 
by  the  hand,  the  leaves  being  picked  off;  but  a  few  are  always  left 
upon  each  branch.  The  number  of  gatherings  made  in  the  same 
year  varies  from  one  to  three,  according  to  the  age  of  the  plant.  It 
is  very  seldom  indeed  that  a  fourth  gathering  is  practised.  In 
China  the  tea  harvest  begins  about  the  middle  of  April,  a  period  at 
which  the  leaf  buds  appear  surrounded  by  a  slight  cottony  down. 
The  first  gathering  is  very  small,  but  it  constitutes  the  highest- 
priced  tea,  the  Shou-chun  or  tea  of  the  first  growth.  The  second 
gathering  takes  place  in  June,  when  the  branches  are  covered  with 
leaves  of  a  pretty  deep  color;  these  leaves  are  very  abundant,  but 
inferior  in  quality  to  the  buds  of  the  former  gathering ;  they  con- 
stitute the  tea  called  Urh-chun,  or  tea  of  the  second  growth.  The 
third  gathering  is  performed  a  month  later,  and  the  produce  passes 
by  the  name  of  the  San-chun,  or  tea  of  the  third  growth.  The 
leaves  are  now  of  a  deep-green  color,  tough,  and  are  manufactured 
into  the  most  common  kinds  of  tea. 

Considerable  plantations  of  tea  are  now  established  in  Assam,  in 
British  India,  and  in  the  Brazils,  and  it  seems  not  improbable  that 
the  plant  may  be  cultivated  at  some  future  day  in  Europe. 

According  to  Guillemin,  who  studied  the  cultivation  and  prepara- 
tion of  tea  in  the  Brazils,  the  leaves  are  dried  as  soon  as  they  are 
gathered.  From  four  to  six  pounds  are  thrown  into  an  iron  pot, 
the  interior  of  which  is  polished,  and  which  may  be  somewhat  more 
than  three  feet  in  diameter,  by  about  a  foot  in  depth.  The  temper- 
ature of  the  pot  is  maintained  at  about  the  boiling  point  of  water;  a 
negro  stirs  the  leaves  in  all  directions  with  his  hand,  until  they  be- 
come quite  soft  and  pliant,  so  that  they  can  be  moulded  into  pellets 
by  movement  between  the  hands.  When  the  leaves  are  in  this 
state,  they  are  thrown  upon  a  tray  made  of  bamboo,  and  strongly 
kneaded  for  a  quarter  of  an  hour,  so  as  to  force  out  a  green  sap  of  a 
disagreeable  taste.  The  kneaded  leaves  are  then  returned  to  the 
pot,  and  dried  completely,  being  all  the  while  stirred  about  with  the 
hand,  being  separated  when  they  stick  together,  and  being  continual- 
ly tossed  up  in  order  to  prevent  them  adhering  or  getting  scorched 
by  remaining  too  long  in  contact  with  the  metal.  During  this  pro- 
cess, which  lasts  for  some  half  hour,  a  large  quantity  of  dust  is 
disengaged,  which  proceeds  from  the  cottony  down  with  which  the 
leaves  are  covered.  By  this  rapid  drying,  the  leaves  crisp  and  curl 
up  of  themselves,  and  acquire  the  appearance  of  the  tea  that  is  in 
every-day  use.  On  being  taken  from  the  drying  pot,  the  tea  is 
thrown  up  )n  a.  sieve  of  a  certain  mesh,  and  the  leaves  which  have 
rolled  themselves  up  into  the  smallest  compass,  and  which  are  those 

♦  Bobinson,  a  Descriptive  Account  of  Assam,  p.  13L 


168  SEEDS. 

which  proceed  from  the  buds,  are  separated  from  the  others  ;  these 
after  having  been  winnowed,  receive  a  new  touch  of  the  fire,  when  they 
acquire  a  leaden-gray  color,  and  constitute  the  lea  of  the  best  quali- 
ty, which  in  the  Brazils  passes  by  the  name  of  Imperial  or  Uchim 
tea.  The  leaves  which  remain  upon  the  sieve  are  heated,  winnowed, 
and  sifted  again,  and  the  produce  is  fine  Hyson  tea ;  and  by  the 
same  means  other  varieties  are  procured,  until  at  length  a  kind  re- 
mains upon  the  sieve  consisting  of  the  leaves  that  have  not  become 
rolled  up,  which  being  added  to  the  broken  particles  derived  from 
the  winnowing  operations,  is  called  family  tea,  because  it  is  consum- 
ed upon  the  spot. 

During,  and  for  some  time  after  the  drying,  tea  exhales  an  herba- 
ceous and  not  very  pleasant  odor,  which  however  becomes  modified 
in  the  course  of  time.  The  aroma  of  the  Chinese  teas  is  said  to  be 
communicated  to  them  by  a  highly  odorous  plant,  which  is  believed 
to  be  the  Oleajiagrans.  It  is  also  said  that  the  green  tea  is  colored 
by  means  of  indigo  ;  but  it  is  possible  that  the  shades  of  color  of  the 
different  kinds  of  tea  depend  solely  upon  the  degree  of  roasting 
which  they  have  undergone.  Guillemin  has  said  nothing  of  the 
produce  of  the  tea  shrub  in  Brazil.  In  China,  according  to  a  man- 
uscript of  M.  Carpena,  a  shrub  with  care  will  produce  annually 
during  thirty  or  forty  years  from  2  lbs.  to  '2,\  lbs.  of  marketable  tea. 

From  the  analysis  of  M.  Mulder,  tea  appears  to  contain  :  1st.  A 
volatile  oil.  2d.  Chlorophylle.  3d.  Wax  and  resin.  4th.  Gum. 
6th,  An  extractive  matter.  6th.  A  coloring  matter.  7th.  Azo- 
tized  substances  analogous  to  albumen.  8th.  Woody  fibre  and  inor- 
ganic salts.  9th.  A  particular  crystalline  principle, — theine  or  cof- 
feine,  which  is  ranked  among  the  vegetable  alkalies,  and  which  is 
also  met  with,  as  implied  by  the  name,  in  coffee  :  this  new  principle 
crystallizes  in  colorless  needles  of  a  silky  aspect  and  bitter  taste. 
It  is  little  soluble  in  alcohol  and  in  ether ;  water  dissolves  about 
^fjXh  of  its  weight,  and  it  sublimes  without  undergoing  decomposi- 
tion ;  it  is  by  sublimation,  in  fact,  that  Mr.  Stenhouse  proposes  to 
obtain  it  from  tea. 

This  is  undoubtedly  the  principle  which  communicates  to  tea  its 
bitter  taste,  and  several  of  its  properties  ;  experiment  has  shown, 
that  when  administered  even  in  considerable  doses  it  produces  no  ill 
eflfect  on  the  animal  economy  ;  different  kinds  of  tea,  as  might  have 
been  presumed,  contain  it  in  different  proportions.  Mr.  Stenhouse 
obtained  from  100  parts  of 

Hyson 1.09  ofCoffeine 

Congou    1.02  " 

Assam 1.37  " 

Twankay,  green 0.98  " 

SEEDS. 

Wheat.  This  valuable  grain  is  the  produce  of  several  kinds  of 
triticum — winter  wheat,  and  spring  wheat,  T.  hybernum^  and  T 
mstivum,  spelter,  T.  Spella,  and  T.  rnonocon. 

Wheat  is  sown  either  upon  a  fallow  or  upon  land  that  has  carried 


I 


WHEAT.  169 

some  torage  crop,  or  such  a  crop  as  beans  and  peas.  It  requires  a 
stiff  rich  soil,  containing  a  certain  proportion  of  calcareous  earth, 
and  abounding  in  organic  matter ;  it  does  not  thrive  well  in  soils 
where  the  sandy  element  predominates  over  the  clayey.  For  seed 
the  best  grain  is  selected  ;  but  this  and  all  other  precautions  do  not 
»:uffice  to  preserve  the  plant  from  many  diseases,  such  as  smut,  rust, 
mildew.  Farmers  are  wont,  before  putting  their  seed  wheat  into 
the  ground,  to  prepare  it  in  various  ways  with  a  view  to  destroying 
the  germs  of  certain  parasites  which  are  believed  to  adhere  to  it  ex- 
ternally. The  process  is  generally  called  pickling,  or  liming,  be- 
cause milk  of  lime,  in  which  the  seeds  are  put  to  steep  for  twelve 
or  fifteen  hours,  is  often  employed  in  its  course.  Means  that  are 
said  to  be  more  efficacious  have  also  been  recommended  :  some 
make  use  of  alum,  others  of  sulphate  of  iron,  sulphate  of  zinc,  sul- 
phate of  copper,  sulphate  of  soda,  and  even  white  oxide  of  arsenic. 
All  these  means  appear  to  conduce  to  the  same  result.  We  employ 
sulphate  of  copper,  which  indeed  is  the  custom  in  a  considerable  part 
of  Alsace,  and  I  can  assure  the  reader  that  our  fields  of  wheat  are 
never  infected.  100  grammes,  or  about  3|  ounces  troy,  are  allowed 
to  a  hectolitre  or  sack  of  nearly  3  bushels  of  wheat ;  the  salt  is  dis- 
solved in  as  much  water  as  is  held  requisite  for  the  submersion  of 
the  grain,  which  is  steeped  in  the  solution  during  about  three  quar- 
ters of  an  hour,  after  which  it  is  thrown  into  baskets  to  drain,  and 
being  then  spread  out  on  the  floor  it  is  dried  before  he'ng  sown. 

The  season  at  which  wheat  is  sown  in  autumn  ought  to  vary  with 
the  climate,  and  nothing  can  be  more  displaced  than  those  precise 
dates  which  are  set  down  by  the  majority  of  writers.  The  great 
point  to  be  held  in  view  is,  that  the  young  plant  may  have  got  a 
certain  length  before  the  frost  sets  in,  that  the  roots  may  have  pene- 
trated to  a  depth  which  shall  protect  them  from  the  severe  cold  of 
the  winter.  In  each  district,  experience  has  already  proclaimed  the 
proper  time  for  sowing,  and  this  can  rarely  or  never  be  departed 
from  without  detriment.  In  the  east  of  France,  in  Alsace,  the  sow- 
ing of  winter  wheat  generally  takes  place  in  the  first  week  in  Octo- 
ber ;  in  the  southern  hemisphere,  in  certain  parts  of  Chili,  for  ex- 
ample, the  wheat  is  sown  in  April,  and  is  exposed  to  the  cold  weather 
of  June,  July,  and  August.  The  quantity  of  seed  sown  may  vary 
from  about  7  pecks  to  18  pecks  and  more  per  acre.  Farmers  gen- 
erally agree,  however,  that  we  have  seed  enough  when  we  employ 
about  2  bushels  to  the  acre  ;  this  is  the  quantity  which  is  used  at 
Bechelbronn  ;  but  in  the  same  district,  and  even  on  contiguous  fields, 
rve  frequently  see  proportions  of  seed  employed  which  vary  in  the 
.•atio  of  from  one  half  to  twice  the  quantity  specified,  without,  so  far 
*s  I  know,  any  sufficient  reason  being  given  for  this  parsimony  or 
jjrodigality.  It  is,  however,  a  question  of  the  very  highest  import- 
mce  to  ascertain  the  proper  quantity  of  seed.  The  question  may 
be  considered  in  two  ways  :  1st.  with  reference  to  the  produce  of  a 
given  extent  of  surface,  and  2d.  with  reference  to  the  produce  from 
ihe  grain  sown.  It  is  quite  certain  that  ir.  sowing  thick,  a  larger 
produce  per  acre  will  be  obtained  than  by  sowing  very  thin  ;  but  on 

15 


170  WHEAT. 

the  other  hand,  thin  sowing  yields  a  larger  i  umber  of  times  the 
quantity  of  seed  put  into  the  ground.  The  reasons  which  should 
guide  us  in  determining  the  dose  of  seed  are  numerous  and  extreme- 
ly complex ;  they  must  evidently  be  taken  in  connection  with  the 
value  of  the  ground  and  of  cnhivation,  the  price  of  wheat  and  of 
straw,  the  cost  of  labor  and  of  manure.  Thus  in  countries  where 
the  rent  of  land  is  extremely  low  it  may  be  a  good  practice  to  scat- 
ter but  a  moderate  quantity  of  seed  over  a  large  extent  of  surface. 
I  remember  a  field  in  the  neighborhood  of  Pampeluna,  where  the 
wheat  was  growing  in  isolated  tufts,  all  extremely  vigorous  and  very 
heavy  in  the  ear  :  the  ground  had  had  but  very  little  preparation ; 
nevertheless,  they  expected  to  gather  from  sixty  to  eiglity  times  the 
seed.  This,  without  doubt,  was  a  profitable  crop  ;  nevertheless,  I 
am  satisfied  that  it  could  not  have  yielded  more  than  from  6^  to  7| 
bushels  per  acre. 

For  the  same  reasons  the  first  settlers  of  the  United  States  must 
have  followed  a  somewhat  similar  mode  of  cultivation.  "  An  English 
farmer,"  says  Washington,  in  a  letter  addressed  to  Arthur  Young, 
"  must  have  a  very  indifferent  opinion  of  our  soil  when  he  hears  that 
with  us  an  acre  produces  no  more  than  from  8  to  10  bushels  of  wheat ; 
but  he  must  not  forget  that  in  all  countries  where  land  is  cheap  and 
labor  is  dear,  the  people  prefer  cultivating  much  to  cultivating  well." 

In  Alsace  we  do  not  reckon  any  crop  profitable  which  yields  less 
than  from  19|  to  about  23  bushels  per  acre ;  and  in  these  circum- 
stances we  do  not  receive  back  more  than  from  9  to  10  times  the  seed. 

Nevertheless,  it  must  be  allowed,  even  in  these  extreme  cases  in 
which  the  value  of  ground  is  so  different,  inasmuch  as  ii  may  vary 
in  the  ratio  of  from  1  to  1000,  that  there  are  certain  limits  with  ref- 
erence to  the  seed  which  must  not  be  passed  ;  and  there  is  without 
doubt  an  opportunity  of  making  a  series  of  curious  and  useful  exper- 
iments, with  the  view  of  ascertaining  the  true  ratios  which  exist 
between  the  produce  and  the  seed.  I  am  well  aware  that  the  results 
of  experiments  of  this  kind  have  already  been  made  public  ;  but  I 
know  also  that  these  data  have  not  been  deduced  from  a  sufficient 
number  of  facts  perfectly  comparable  with  one  another,  and  noted 
under  a  varirty  of  climatic  influences  ;  in  a  word,  that  they  are  not 
such  as  they  ought  to  be,  to  put  an  end  to  the  uncertainty  which  still 
exists  in  the  minds  of  the  best-informed  farmers  and  rural  economists 
upon  the  subject. 

In  Europe,  the  wheat  that  is  sown  in  autumn  generally  stands 
upon  the  ground  for  from  nine  to  ten  months.  The  time,  however, 
varies  considerably  with  the  climate  ;  in  the  Andes,  it  is  in  propor- 
tion to  the  proper  temperature  of  each  place. 

Wheat,  which  is  now  an  important  article  of  agricultural  produce 
in  America,  was  introduced  from  Europe  very  shortly  after  the  Con- 
quest The  first  particles  of  wheat  sown  in  Mexico  before  1530,  are 
said  to  have  been  found  by  a  negro  belonging  to  Fernando  Cortez 
among  the   rice  destined  for  provision  to   the  army.*       Wheat 

•  Hamboldt's  Essay  on  New  Spain,  vol.  lU 


WHEAT. 


171 


was  brought  into  Quito  by  a  Fleming,  Father  Jose  Rixi,  a  monk 
of  the  order  of  St.  Francis.  I  was  shown  in  the  Convent  of  St. 
Francis,  the  vessel  in  which  the  first  seed  is  said  to  liave  come  from 
Europe. 

In  Mexico,  where  the  ground  can  be  irrigated,  and  this,  all  things 
else  being  the  same,  always  yields  the  best  crops,  wheat  is  watered 
at  two  different  periods — when  it  has  sprung  and  when  it  is  shooting 
into  ear.  According  to  M.  de  Humboldt,  who  has  collected  so  much 
that  is  interesting  upon  the  agriculture  of  New  Spain,  the  richness 
of  the  harvest  is  truly  surprising;  irrigated  soils  often  yield  from 
40  to  60  times  the  seed ;  16  for  1  is  reckoned  a  middling  crop,  and, 
taking  the  whole  of  Mexico,  the  mean  produce  may  be  estimated  at 
from  22  to  25  for  1. 

The  cultivation  of  wheat  is  especially  lucrative  in  districts  which 
enjoy  a  mean  temperature  of  from  18°  to  19"  C,  (65"  to  67"  F.  :)  yet 
it  may  be  pursued  amid  plantations  of  coffee-trees  and  sugar-canes, 
although  I  doubt  whether  it  can  there  be  extremely  productive.  The 
extreme  limits  of  the  growth  of  wheat  in  the  Cordilleras,  according 
to  my  own  observations,  correspond  with  tlie  mean  temperatures  of 
from  12"  to  23.5°  C.  (54  to  75°  F.)  M.  Codazzi  estimates  at  37  for 
1  the  mean  produce  of  vVheat  in  Venezuela. 

The  hectolitre  of  wheat  in  France  (22.009  gallons,  something  less 
than  a  sack  of  three  bushels  English)  is  held  to  weigh,  on  an  ave- 
rage, 169.4  lbs.,  or  61.6,  say  6U  lbs.  per  bushel;  but  this  weight 
varies  according  to  the  quality  of  the  grain  between  56  and  64  lbs. 
the  bushel. 

The  following  is  a  table  of  the  mean  produce  of  the  wheat  crop 
in  different  countries,  from  documents  that  may  be  relied  on : 


Localities. 


Germany:  Moeglin 

Lavanthal 

Saaifelden 

Lombardy  :  irrigated  lands 

"  non-irrigated  lands 

Average  of  Venetian  Lombardy.... 

England  :  the  best  soils ■ 

"  average  

Brabant  and  Flanders 

Prance:  Alsac«^  (after  tobacco) 

"  "       Bechelbronn • 

Environs  of  Paris 

"         Oise 

America  r  (East  of  the  AUeghanics) 

"  rich  lands 

"  middling  ditto 

Mississippi:  rich  lands 

"  middling  ditto 

Venezuela  (Valley  of  Aragua) 

"  temperate  regions 


Produce  per 


acre  (seed 

Authorities. 

deducted.) 

Bushels. 

26.7 

Thaer. 

22.0 

Burger. 

18.0 

Lurzer. 

25.6 

Burger. 

1.5.9 

Dandolo. 

11.0 

Verra. 

15.9 

Burger. 

34.0 

Arthur  Young. 

23.0 

Arthur  Young. 

25.0 

Schwertz. 

29.0 

Schwertz. 

22.3 

Lebel  and  Boussing. 

25.2 

Daillv. 

2L5 

Official  statistics. 

^      35.0 

N 

i       9.0 
r     44.2 

VBlodget. 

27.0 

44.0 

Humboldt. 

14.0 

Codazzi. 

172  WHEAT. 

The  cereals,  besides  their  principal  produce,  their  farinaceous 
seeds,  yield  another,  which  is  of  great  importance  in  rural  economy; 
this  is  straw,  which  no  European  agricultural  establishment  could 
do  without.  After  having  been  used  as  food  and  as  litter  for  cattle, 
it  is  returned  to  the  ground  as  manure,  and  contributes  powerfully 
in  preventing  the  exhaustion  of  the  soil,  which  the  cultivation  of 
wheat  always  produces.  The  quantity  of  straw  which  can  be  recl^- 
oned  on  in  a  farm,  is,  of  course,  in  proportion  to  the  soil  under  white 
crops.  The  relative  weight  of  grain  and  straw,  however,  varies 
considerably  according  to  circumstances  ;  in  a  wet  year,  for  instance, 
the  wheat  crop  contains  a  relatively  large  proportion  of  straw,  and 
a  small  proportion  of  grain;  in  dry  years  the  contrary  relation  ob- 
tains. Lands  recently  and  abundantly  manured,  yield  a  larger 
quantity  of  straw  than  clover  breaks.  Thick  sowing  always  yields 
a  large  quantity  in  contrast  with  the  grain  ;  lastly,  climate  exerts 
the  most  marked  influence  upon  the  two  kinds  of  produce  which  we 
are  considering.  The  differences  which  are  observed  between  one 
year  and  another,  in  the  same  districts,  in  consequence  of  very  dif- 
ferent meteorological  conditions,  are  not  less  remarkable.  I  shall 
quote  a  single  instance.  The  years  1840,  1841,  and  1842  gave  us 
crops  of  grain  at  Bechelbronn  which  were"  far  from  excellent  ;  in 
the  first  the  rains  were  too  abundant,  and  in  the  second  the  drought 
was  too  long  continued.  In  these  opposite  circumstances,  the  weight 
of  the  straw  to  that  of  the  grain  was — 

In  1840-41    :  :    100    :    24 
In  1841-42    :  :    100    :    90 

The  latter  harvest,  in  fact,  occasioned  a  complete  dearth  of  litter  in 
cur  establishment.  In  ordinary  years  we  procure  about  38  of  grain 
for  100  of  straw,  a  relation  which  agrees  with  those  that  have  been 
reported  by  different  observers,  who  vary  in  their  calculations  from  33 
and  35  to  41,  44,  and  50  of  grain  to  100  parts  of  straw. 

In  the  cereals  the  amylaceous  matter,  which  constitutes  the  princi- 
pal part  of  the  seed,  is  surrounded  by  a  flexible  perisperm,of  the  nature 
of  woody  tissue.  The  object  of  grinding  is  to  break  this  case  and  to 
reduce  the  interior  of  the  grain  to  powder.  In  France,  the  grinding 
of  wheat  is  performed  by  a  succession  of  operations ;  in  England  it  is 
completod  at  once.  The  French  mode,  however,  appears  to  yield 
the  largest  quantity  of  fine  flour. 

English.  French. 

Fine  flour ^('70  66),. 

Secondflour 14  j'-*  8\'* 

Bran 26  23 

Loss 2  3 

The  proportion  of  flour  furnished  by  the  cereals  does  not,  however, 
depend  alone  upon  the  mode  of  grinding,  but  also  upon  the  nature  of 
the  grain.  Wheat,  for  instance,  of  different  kinds,  yields  78,  83,  and 
85  J  per  cent,  of  flour. 

Speller.  This  grain  is  so  firmly  enclosed  in  the  husk  that  it  can- 
not be  freed  by  threshing ;  so  that,  in  the  countries  where  this  grain 
is  grown,  the  mills  are  provided  with  an  apparatus  for  husking  it 


WHEAT.  173 

Schwertz  made  many  experiments  in  Wurtemberg  to  determine  the 
quantity  of  flour  yielded  by  spelter,  and  he  found  that  from  100  of  grain 
he  obtained  90  of  husked  grain,  and  8.7  of  bran  ;  there  was  a  loss  of 
1.3.  The  quality  of  the  flour  always  varies  according  to  the  wheal 
from  which  it  is  procured  :  it  contains  moisture  in  variable  propor- 
tions, gluten  in  variable  proportions,  and,  finally,  various  quantities 
of  woody  matter.  The  wheat  of  the  south  is  harder  and  tougher  than 
that  of  the  north,  and  appears  richer  in  azotized  principles  ;  as  it  con- 
tains less  moisture,  it  also  keeps  better  ;  it  is,  undoubtedly,  in  conse- 
quence of  the  large  quantity  of  water  which  our  northern  wheats 
contain,  that  we  meet  with  such  indifferent  success  when  we  attempt 
to  keep  them  for  any  length  of  time  in  our  granaries.  The  wheat  of 
Alsace,  for  example,  frequently  contains  from  16  to  20  per  cent,  of 
moisture  ;  a"d  I  have  ascertained,  by  various  experiments,  that  it  is 
almost  impossible  to  keep  it  without  change,  in  vessels  hermetically 
sealed.  To  secure  its  keeping,  the  proportion  of  water  must  be  re- 
duced to  from  8  to  10  per  cent.,  and  this  is  nearly  the  quantity  of 
moisture  contained  in  the  hard  and  horny  wheat  of  warm  countries 
I  am  therefore  of  opinion  that  we  shall  never  succeed,  in  these  coun 
tries,  in  keeping  wheat  for  any  length  of  time — in  the  magazines  of 
fortified  towns,  for  example — whatever  care  be  taken. 

The  flour  of  the  cereals,  particularly  that  of  wheat,  absorbs  a  largo 
quantity  of  water,  and  forms  a  paste,  which  is  by  so  much  the  firmer 
and  more  elastic,  as  the  flour  contains  a  larger  proportion  of  gluten  ; 
the  azotized  principle  of  wheat  has,  in  fact,  the  remarkable  property 
of  being  extensible  like  a  membrane,  when  it  is  moist,  and  this  prop- 
erty it  communicates  to  the  whole  of  the  paste  or  dough.  In  order 
to  be  brought  into  the  state  of  dough  fit  for  making  bread,  flour  will 
absorb  from  55  to  70  per  cent,  of  water.  The  quantity  of  bread  ob- 
tained necessarily  depends  upon  the  heat  and  length  of  exposure  in 
the  oven  ;  but,  in  a  general  way,  from  100  of  flour,  130  of  the  best 
white  bread  of  Paris  is  procured.  In  the  country,  the  bread  is 
generally  less  baked  than  in  Paris  or  London,  and  therefore  retains 
more  water  ;  so  that  from  100  of  flour,  140, 145,  and  146  of  bread  are 
made :  thus,  admitting  16  per  cent,  of  moisture  as  existing  in  wheat 
originally,  we  have  of  absolute  dry  matter  64|,  57,  and  56  in  different 
kinds  of  bread. 

Bread  is  by  so  much  the  more  nutritious  as  it  is  made  from  flour 
containing  a  larger  proportion  of  gluten  ;  to  add  any  starch  therefore 
is  to  prejudice  the  interests  of  the  consumer;  nevertheless  it  is  the 
practice  to  do  so  almost  openly ;  when  potato  starch  is  at  a  low 
price,  the  adulteration  frequently  begins  with  the  miller  and  is  ex- 
tended under  the  baker.  The  quantity  of  gluten  contained  in  differ- 
ent kinds  of  wheat  varies  greatly.     Vauquelin  found  in  the — 

Gluten 

Flour  of  French  wheat 11.0 

Flour  from  hard  Odessa  wheat  14.6 
Flour  from  soft  Odessa  wheat  12.0 
Fiour  from  the  baker's 10.2 

The  method  of  analysis  employed  by  Vauquelin,  whose  resultt 

15* 


Starch. 

Sugar. 

Gum 
or  dextrine. 

Water. 

Bran. 

71.5 

4.7 

3.3 

10.9 

.56.5 

8.5 

4.9 

12.0 

2.3 

62.0 

7.6 

5.8 

10.0 

1.2 

72.8 

4.2 

2.8 

10.0 

174  WHEAT. 

are  given  above,  by  means  of  washing,  is  how^ever  far  from  being 
very  accurate  ;  it  is  impossible  to  prevent  the  loss  of  some  gluten 
which  passes  with  the  starch,  and  the  vegetable  albumen  is  entirely 
lost  by  reason  of  its  solubility  in  water :  and  then  to  dry  gluten  is  a 
very  long  and  delicate  process  ;  and  if  we  would  pretend  to  any  de- 
gree of  accuracy,  we  must  ascertain  the  quantity  of  fatty  matter 
contained  in  the  samples.  I  therefore  thought  that  with  reference 
to  the  azotized  principles  particularly,  the  better  way  would  be  by 
proceeding  to  ascertain  these  by  immediate  ultimate  analysis. 

The  four  azotized  principles  which  we  have  already  admitted 
have  very  nearly  the  same  elementary  composition  ;  the  mean  propor- 
tion of  azote  in  each  is  0.16.  With  this  datum,  it  is  evident  that  if  a 
particular  sample  of  flour  is  found  to  contain  0.04  of  azote,  it  may  be 
inferred  that  this  azote  represents  0.25  of  gluten,  albumen,  fibrine, 
and  caseine,  dried  at  140°  C.  (284°  F.,)  and  as  these  are  the  most 
valuable  elements  in  flour,  I  took  the  pains  to  ascertain  their  pro- 
portion in  a  considerable  number  of  vaHeties  of  wheat,  the  whole  of 
which  were  grown  in  the  same  year,  in  the  same  soil,  which  was 
well  manured,  and  under  climatic  influences  that  were  identical ;  nor 
did  I  restrict  myself  to  the  azotized  matters  of  these  samples  ;  I  also 
endeavored  to  ascertain  the  precise  relative  quantities  of  bran  and 
of  flour.  The  following  table  contains  the  results  of  my  experi- 
ments. 


WHEAT. 


175 


1 

grayish,  coarse. 

soft. 

very  coarse. 

yellow,  coarse. 

very  coarse. 

yellowish,  soft. 

coarse. 

very  white,  soft. 

yellowish,  rough. 

somewhat  coarse. 

white,  very  soft. 

yellowish,  soft. 

white,  very  soft. 

yellowish, 

white,  very  soft. 

white,  rather  rough. 

soft,  white. 

white,  extremely  fine.  : 

yellow,  very  coarse. 

white,  very  soft. 

yellowish,  very  soft. 

yellow,  coarse. 

ditto. 

white,  very  soft. 

1 

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I 

.S 

small,  thin. 

middling. 

very  large. 

horny,  long. 

small,  brown. 

middling. 

reddish. 

yellow,  fine. 

small,  hard. 

hard. 

reddish. 

large. 

soft. 

pretty  hard. 

soft. 

white,  hard. 

ditto. 

small. 

gray,  hard. 

yellow,  large. 

wrinkled. 

small,  red. 

hard,  very  large. 

well-formed. 

t 

1 

Triticum  spelta  rufa  mutica 
Small  spelter,  T.  monococon 

Great  spelter 

Mecca  wheat 

Bearded  wheat 

Winter  wheat,  T.  hybernum      . 
Common  wheat  (mouret)  . 
Reyel  wheat    .... 
Red  Egyptian  wheat    .... 
A  large  wheat  growing  in  4  ranks 
Fine  red  wheat  of  Roussillon      . 

Red  Marcel  wheat 

Dantzic  wheat 

Wheat  from  the  North       .     .     . 
Fine  red  wheat  (pays  de  Foix) 

Smyrna  wheat 

Bengal  wheat 

Tangarok  wheat 

Hard  African  wheat     .... 

Cape  wheat 

Russian  wheat 

Sicilian  wheat 

Giant  St.  Helena  wheat     .     .     . 
Subernac  wheat  (Pyrenees)   .    . 

176  WHEAT. 

The  quantity  of  gluten  ind  albumen  contained  in  these  samples  of 
flour  is  much  larger  than  that  usually  indicated  ;  I  have  given  rea- 
sons which  explain,  to  a  certain  extent,  this  difference.  I  ought  to 
add,  however,  that  the  varieties  of  wheat,  the  flour  of  which  was 
analyzed,  were  all  grown  in  the  rich  soil  of  the  garden,  a  circum- 
stance which,  as  Hermbstadt  has  shown,  exerts  the  most  powerfu. 
influence  in  increasing  the  quantity  of  gluten  in  wheat. 

It  was  already  known,  from  the  experiments  of  Tessier,  that  the 
proportion  of  gluten  in  the  same  species  of  wheat  might  vary  in  the 
ratio  of  from  12  to  36  per  cent,  of  the  weight  of  the  flour,  according 
to  the  nature  of  the  soil  and  the  quantity  of  manure.  But  it  was 
Hermbstadt  who  first  made  truly  comparative  observations  on  the 
action  of  the  excrements  of  diflferent  animals  on  the  culture  of  the 
cereals. 

The  excrements  made  use  of  by  this  able  cultivator  in  his  inquiries 
w^ere  always  dried  in  the  air  at  a  temperature  of  12|°  C.  (54^°  F.,) 
and  equal  areas  of  the  same  soil  were  sown  with  equal  weights  of 
winter  wheat,  and  had  a  similar  dose  of  manure  of  one  kind  or  an- 
other spread  over  them.  One  hundred  parts  of  the  flour  obtained 
from  wheat  thus  grown  yielded  : 

Bran,  soluble  mai- 

-  Gluten.  Starch,  ter  and  moiiture. 

With  human  urine 35.1  39.3  25.6 

"      bullock's  blood 34-2  41-3  25.5 

"     human  excrement 33.1  41.4  25.5 

"      sheep's  dung 22-9  42.8  34-3 

"      goat's  ditto 32.9  42.4  24.7 

"     horse  ditto 13.7  61-6  24-7 

"      pigeon's  ditto 12.2  63-2  24-6 

"      cow's  ditto 12.0  62.3  25.7 

Soil  not  manured 9-2  66.7  24-1 

It  is  apparent,  therefore,  that  in  general,  for  the  exception  onl 
refers  to  the  pigeon's  and  the  horse  dung,  the  wheat  grown  in  groun 
manured  with  the  most  highly  azotized  matters  yields  the  target 
quantity  of  gluten. 

By  way  of  adding  to  and  confirming  these  conclusions  of  Hermb 
stadt,  I  shall  give  the  results  of  an  experiment  of  my  own,  made  i< 
1836,  in  which  the  same  variety  of  wheat  was  grown  in  the  opev 
field,  and  in  garden  ground  very  highly  manured.  The  grain  wjm 
analyzed  after  having  been  dried  at  110°  C,  (230"  F.,)  and  gave  : 

From  the  open  field.        From  the  garilen  gnuad. 

Carbon 46-10  45.51 

Hydrogen 5.80  5.67 

Oxygen 43.40  43.00 

Azote 2.29  3.51 

Ashes 2.41  2.31 

100.00  100.00 

In  the  produce  of  the  garden  there  were  21.94 — very  nearly  22 
per  cent,  of  gluten  and  albumen  ;  in  that  of  the  open  field  no  more 
than  14.31  per  cent,  of  the  same  principles. 

Davy  was  of  opinion  that  the  wheat  of  warm  climates  was  richer 
in  azoti'/ed  principles  than  that  of  temperate  lands.  Southern  coun- 
tries are  known  to  produce  harder,  tougher  grain,  the  flour  of  whicb 


RYE.  171 

contains  more  gluten  than  the  soft  and  more  friable  wheat  of  the 
north  ;  and  the  inquiries  of  M.  Payen  appear  to  bear  out  the  conclu- 
sion of  the  illustrious  English  chemist.  M.  Payen,  in  fact,  found  in 
the  hard  wheat  of  Africa  3.00  of  azote,  equivalent  to  18.7  ;  and  in 
that  of  Venezuela  3.50  of  azote,  equivalent  to  21.9  of  gluten  and 
albumen.  The  experiments  quoted  above,  however,  prove  that  we 
may  have  wheat  grown  in  Europe  fully  as  rich  in  azotized  elements 
as  any  that  is  grown  between  the  tropics ;  the  influence  of  the  soil 
in  this  direction  is  probably  more  than  the  influence  of  climate. 

In  all  the  analyses  of  wheaten  and  other  flour  published  up  to  the 
present  time,  we  find  no  mention  made  of  the  fatty  matters  which 
they  contain  ;  and  late  views  in  regard  to  the  special  part  which 
ihese  matters  play  in  nutrition  make  it  very  necessary  to  supply  the 
omission.  A  ong  with  MM.  Dumas  and  Payen,  I  therefore  deter- 
mined the  quantity  of  fatty  matter  contained  in  a  considerable  num- 
ber of  the  vegetables  and  vegetable  substances  used  as  food,  from 
which  it  appears  that  grain  of  diflferent  kinds  contains  from  2  to  10 
per  cent,  of  oil.  One  hundred  parts  of  winter  wheat  gathered  at 
Bechelbronn  lost  14.5  of  water  by  drying  at  110'  C,  (230°  F.,)  and 
therefore  contained  85.5  of  dry  matter.  100  of  this  dry  wheat  gave 
13.7  of  bran  and  86.3  of  flour. 

Various  analyses  showed  the  composition  of  this  wheat  and  its 
parts  to  be  as  follows  : 

Dry  matter.  Gluten  and     Starch. 

Albumen. 

Bran 20.0 

Flour 13.4  73.2  5.6  4.2  2.1  1.5 

Wheat 14.3  63.2 

Rye,  {Secale  cereale.)  Rye  is  an  important  article  ot  food,  par- 
ticularly in  the  north  of  Europe,  where  the  people  live  upon  it  almost 
entirely.  It  is  a  very  hardy  plant,  and  will  thrive  in  soils  which  are 
altogether  unfit  to  grow  wheat.  In  the  husbandry  of  the  north  this 
grain  occupies  the  place  of  wheat  in  the  south  :  it  requires  much 
the  same  treatment,  and  stands  upon  the  ground  for  nearly  the  same 
length  of  time.  The  bushel  of  rye  weighs  on  an  average  about  60  lbs. 
avoird.  The  usual  quantity  of  seed  sown  is  from  10  to  11  pecks 
per  acre,  and  the  produce  per  acre,  the  seed  being  deducted,  has 
been  stated  as  follows  : 

Bushels. 

Brabant 23.0 

Flanders 32.4 

Austria 206 

England 22.0 

France 19.0 

The  German  agriculturists  say,  that  the  weight  of  the  straw  to 
the  weight  of  the  rye  produced  is  in  general  as  100  is  to  47  ;  others 
say  as  100  is  to  50,  and  some  have  taken  it  even  as  high  as  100  to 
33.  The  relation  seems  to  differ  extremely  in  different  years.  At 
Bechelbronn,  for  example,  in  1840-41  we  had  63  of  grain  to  100  of 
straw;  in  1841-42  we  had  but  25  of  grain  to  100  of  straw. 

Rye  yields  flour  that  is  not  so  white  nor  so  fine  as  that  of  wheat, 


Glucose. 
(Su^ar.) 

Gum. 

Fatty 
matter. 

Woody 
tissue. 

5.6 

28.8 
4.2 
12.i 

55 
2.1 
1.6 

45.7 
7.5 

178  BARLEY OATS. 

which  is  in  consequence  of  the  woody  covering  of  the  ofraih  getting 
ground,  in  great  part,  in  the  mill.  If  but  from  50  to  65  purts  per 
cent,  of  flour  be  taken  from  rye,  it  is  white  and  looks  well.  The 
dough  made  with  rye  flour  is  not  very  adhesive  ;  it  contains  little 
vegetable  fibrine,  the  azotized  principle  which  gives  gluten  its  elas- 
tic properties.  It  is  this  want  of  vegetable  fibrine  which  renders  it 
more  difficult  to  make  good  light  bread  of  rye  than  of  wheaten  flour, 
although  experiment  shows  that  rye  flour  of  the  first  quality  will  form 
as  large  a  proportion  of  bread  as  wheaten  flour ;  100  of  rye  flour 
have  given  145  of  bread. 

Rye  bread  is  more  hygrometric  than  that  of  wheat,  and  conse- 
quently remains  for  a  longer  time  soft  and  fresh.  Rye  generally 
contains  24  of  bran  to  76  of  flour  ;  by  drj^ng  at  230  F.  it  loses  about 
17  per  cent,  of  water.  Analyses  of  a  dried  sample  grown  at  Bechel- 
bronn  yielded  : 

Gluten  and  albumen  (azotized  principles  united) 10.5 

Starch 64.0 

Fatty  matters 3.5 

Sugar  (glucose  7) 3.0 

Gum  ]1.0 

Woody  matter  and  salts  (phosphates) 6.0 

Loss 2.0 

looTo 

Barley,  {Hordeum  vulgare.)  The  usual  produce  of  barley  varies 
much  from  15  or  20  to  50,  60,  and  even  70  bushels  per  acre  ;  the 
average  for  France  is  stated  at  about  43|  bushels  ;  and  the  weight 
of  the  bushel  may  be  taken  on  an  average  at  about  504  lbs.  The 
ratio  of  the  straw  to  the  grain  varies  very  much,  but  may  be  taken 
generally  at  that  of  100  to  50.     Barley  contains  : 

Of  flour 68.6 

Bran  18.4 

Water .13.0 

100.0 

Dried,  this  grain  gave  0.0214  of  azote,  which  represents  13.4  per 
cent,  of  gluten  and  other  azotized  principles. 

Oats,  {Avena  sativa.)  When  oats  yield  43  or  44  bushels  per  acre, 
the  crop  is  a  fair  one.  At  Bechelbronn  we  have  frequently  had  up- 
wards of  45  bushels  per  acre.*  Schwertz  states  the  relation  between 
the  straw  and  the  grain  as  100  is  to  60. 

Some  oats  gathered  in  1841-42  yielded  78  of  meal  and  22  of 
husk  per  cent. 

One  hundred  parts  of  these  oats  lost  by  drying  at  230°  F. ,  20.8 
of  water  ;  thus  dried,  analysis  showed  that  they  contained : 

Of  starch 46.1 

"  gluten,  albumen,  to 13.7 

"  fatty  matter 6.7 

"  sugar  (glucose) 6.0 

"  gum 3.8 

"  woody  matter,  ashes,  and  loss «  21.7 

100.0 

♦  This  would  be  reckoned  a  poor  croo  in  the  North  of  England  and  Scotland,  whrf» 
10^  tW,  and  even  100  bushels  of  oate  pet  \cn  are  frequently  grown*— Eko.  Ed 


MAIZE.  17& 

Maize,  {Zea  mais.)  This  is  the  true  wheat  of  the  Americans, 
and  it  is  now  generally  avowed  that  the  plant  is  a  native  of  the 
New  World.  It  is  also  well  known  that  maize  was  introduced  into 
Spain  long  before  potatoes.  Oviedo  states  in  his  work,  printed  in 
1525,  that  he  had  seen  it  growing  in  Andalusia  and  the  neighbor- 
hood of  Madrid.  The  cultivation  of  this  useful  plant  was  observed 
everywhere  on  the  discovery  of  America  by  Europeans,  from  the 
most  southern  parts  of  Chili  to  Pennsylvania  in  the  north  ;  and  in 
the  neighborhood  of  the  equator,  from  the  level  of  the  sea  to  the 
high  table-lands  of  the  Andes.  Garcilasso  gives  a  particular  de- 
scription of  the  procedure  followed  by  the  Incas  in  the  cultivation 
of  this  plant,  the  kind  of  manure,  &c.  At  Cusco  the  Indians  ma- 
nured with  human  excrement  dried  and  reduced  to  powder.  On  the 
coasts  they  employed  in  one  place  guano ;  in  others,  as  the  dusty  and 
sterile  soils  of  Attica,  Atiquiba,  &c.,  they  made  use  of  the  ofFal  of  fish. 

The  uses  of  maize  are  very  numerous.  In  America  it  is  made 
into  cakes,  which  are  a  substitute  for  bread ;  by  fermentation  a 
vinous  liquor  is  prepared  from  it  called  chicha.  Before  the  conquest, 
the  Mexicans  manufactured  a  sirup  from  the  expressed  juice  of  the 
stems.  In  describing  to  Charles  V.  the  various  articles  of  provision 
that  were.met  with  in  the  march  to  Tlatclolclo,  Cortez  says,  "  They 
sold  us  the  honey  of  bees,  wax,  and  honey  from  the  stems  of  the 
maize  plant."  Maize  when  ground  and  boiled  makes  a  kind  of 
pudding  in  universal  use,  and  the  ear,  when  nearly  ripe,  whether 
boiled  in  water  or  roasted  in  the  ashes,  is  held  a  luxury  by  all  class- 
es. In  the  tropical  Cordillera  maize  is  advantageously  cultivated 
from  the  level  of  the  sea  to  the  height  of  9186  feet  above  it ;  that  is  to 
say,  it  thrives  in  temperatures  which  vary  between  14°  and  27.5°  C. 
(57.5°  and  81.5°  F. ;)  this  circumstance  explains  its  very  general 
introduction  into  Europe. 

Maize  succeeds  on  all  soils  when  they  are  properly  manured  ; 
I  have  seen  beautiful  crops  upon  the  most  sandy  soils  and  upon  the 
stifFest  clays  ;  it  requires  much  the  same  management  as  our  ordi- 
nary grain  crops ;  the  climate  alone  should  decide  as  to  whether  its 
introduction  into  a  particular  district  is  opportune  or  not ;  a  certain 
degree  of  heat  is  necessary  to  ripen  it,  and  above  all,  the  cold  to 
which  it  is  exposed  must  not  be  too  severe.  It  is  for  this  reason, 
that  in  the  east  of  Europe  the  maize  is  sown  in  spring,  when  there  is 
no  longer  any  apprehension  of  frost ;  there  would  be  a  real  advan- 
tage in  sowing  late,  were  it  not  for  fear  of  the  frosts  of  autumn  at 
the  season  of  ripening.  The  susceptibility  of  maize  to  frost  and 
climate  generally,  appears  to  me  very  analogous  to  that  of  the  vine  ; 
and  I  doubt  whether  it  would  be  wise  to  attempt  its  cultivation  on  the 
great  scale  where  the  grape  does  not  ripen  in  ordinary  years. 

Maize  is  sown  either  with  the  dibble  or  with  the  hand,  following 
a  furrow  opened  by  the  plough ;  I  believe  that  it  ought  never  to  be 
sown  broadcast,  for  it  is  a  plant  that  requires  room  ;  it  is  only  in  the 
hottest  countries  that  the  drill  system  is  less  necessary.  In  Alsace  the 
drills  are  about  2^  feet  apart,  and  the  seeds  are  sown  at  the  distance 
of  abou'-  &  foot  from  each  other.     This  very  considerable  spaco  left  be* 


180  MAIZE. 

tween  the  maize  plants  appears  to  authorize  the  general  custom  that 
prevails  of  interposing  som3  other  crop  in  the  fields  under  Indian 
corn  ;  that  which  is  most  generally  interposed  is  either  the  dwarf 
haricot  or  the  potato.  I  observed  the  same  custom  in  the  more  tem- 
perate valleys  of  the  Andes,  where  it  is  almost  as  necessary  as  in 
Europe  to  leave  free  spaces  between  the  plants  to  give  them  air  and 
sun  ;  but  the  plant  is  cultivated  alone  in  the  hotter  regions.  Soon 
after  maize  has  sprung  it  receives  a  first  hoeing,  and  after  it  has  got 
to  a  certain  height,  a  second  ;  in  Alsace,  for  instance,  it  is  custom- 
ary to  hoe  towards  the  end  of  June  ;  but  I  never  saw  any  operation 
of  the  kind  performed  between  the  tropics  :  the  only  care  they 
seemed  to  take  of  their  fields  of  Indian  corn,  was  to  pull  up  foul  weeds 
In  Europe  it  is  usual  to  take  away  the  sprouts  which  rise  beside  the 
principal  stem  ;  this  precaution  is  also  unnecessary  in  equatorial 
countries  where  the  ground  is  fertile ;  the  more  lateral  stems  that 
rise,  the  better,  as  they  all  become  richly  laden  with  grain.  I  may 
also  say  as  much  for  the  system  of  topping  which  prevails  among  us, 
tiiat  system  which  consists  in  removing  the  extremity  of  the  stem 
which  bears  the  male  flowers  after  the  fecundation  has  been  efifected. 
The  leaves  and  heads  of  stems  which  are  obtained  by  this  operation, 
compose  a  forage  by  no  means  to  be  despised. 

The  time  during  which  the  crop  of  maize  remains  on  the  ground, 
is  greatly  influenced  by  the  mean  temperature  of  the  climate  ;  in  hot 
intertropical  countries,  the  grain  ripens  in  less  than  three  months, 
and  there  are  even  farms  upon  which  four  considerable  crops  are 
gathered  in  the  course  of  the  year.  On  the  temperate  plateau  or 
table-land  of  Bogota,  the  plant  ripens  in  six  months ;  in  Alsace  about 
the  same  length  of  time  is  required,  although  at  Bechelbronn,  in  1836, 
the  maize  which  was  sown  on  the  1st  of  June  was  gathered  ripe  on 
the  1st  of  October.  Maize  is  dried  either  in  exposing  the  spikes 
stripped  of  their  covering  upon  the  floor  of  a  well-ventilated  gra- 
nary, or  by  hanging  them  up  in  bunches  or  sheaves  under  sheds,  or 
under  the  eaves  of  the  house.  In  warm  countries  the  drying  is 
accomplished  by  one  or  two  days'  exposure  to  the  sun,  after  which 
the  spikes  are  stored.  The  maize  is  freed  from  the  stem  with  the  hand 
in  small  farms,  with  the  flail  in  larger  establishments.  In  America 
the  operation  is  never  done  until  the  moment  when  the  grain  is  want- 
ed, as  it  is  said  that  the  grain  is  less  subject  to  be  attacked  by 
insects  v/hen  it  is  kept  in  the  ear.  When  animals  are  fed  on  maize, 
hey  are  accustomed  to  separate  it  for  themselves. 

The  produce  in  Indian  corn  varies  greatly,  as  appears  by  the  fol* 
lowing  table,  in  different  countries : 

Countriei.  Produce  in  butbeli 

per  acr«. 

Lavanthal 81 

Carinthia 55 

Austria  and  Moravia 24 

Hungary  and  Croatia 42 

Tuscany % 

France  (climate  of  PiVs) 29 

Alsace 43 

Venezuela 147 


MAIZE.  181 

By  far  the  finest  crops  of  Indian  corn  in  America  are  obtained  upon 
breaks  of  virgin  seil.  I  do  not  hesitate  to  say  that  the  husbandman 
gains  from  six  hundred  to  seven  hundred  times  his  seed  under  such 
circumstances.  The  mode  of  proceeding  upon  these  breaks,  which 
I  have  frequently  witnessed,  deserves  to  fix  attention  for  a  moment. 

The  planter  chooses  the  end  of  the  rainy  season  for  cutting  down 
the  trees  and  the  brushwood  :  every  thing  remains  where  it  falls 
until  it  is  sufficiently  dry  ;  fire  is  then  set  to  the  heap,  and  the  burn- 
ing extends  and  lasts  even  for  weeks;  all  the  smaller  branches  are 
completely  consumed,  nothing  but  the  charred  trunks  of  the  larger 
trees  remain.  As  the  rainy  season  is  about  to  return,  a  man,  with 
a  pointed  stick  in  his  hand,  goes  over  the  burnt  surface,  making  a 
hole  of  no  great  depth  at  intervals,  into  which  he  throws  two  or 
three  particles  of  Indian  corn,  over  which  he  draws  a  little  earth,  or 
rather  ashes,  by  a  slight  motion  of  his  foot.  This  primitive  mode 
of  sowing  terminated,  the  planter  takes  no  further  heed  of  the  crop  ; 
his  habitation  is  often  so  remote,  that  he  never  visits  it  until  harvest 
time  :  the  rain  and  the  climate  do  all  the  work.  It  is  unnecessary 
to  hoe,  the  burning  having  destroyed  all  the  plants  that  were  indi- 
genous to  the  soil ;  nothing  rises  but  the  grain  which  has  been  sown. 
In  such  fields,  stems  of  Indian  corn  are  frequently  seen  of  the  height 
of  from  twelve  to  fourteen  feet.  It  rarely  happens  that  more  than 
three  consecutive  crops  are  taken  from  the  burnt  soil ;  and  the  last, 
though  still  very  superior  to  any  thing  which  we  can  obtain  by  our 
regular  husbandry,  is  not  to  compare  with  the  first.  As  there  is  no 
want  of  forest,  it  is  held  preferable  to  make  a  fresh  break. 

Taking  the  seed  as  unity,  it  is  found,  from  documents  now  pos- 
sessed, that  1  of  seed  will  yield — in  Mexico  (an  indifferent  harvest) 
150 ;  in  New  California  (beyond  the  tropics)  80  ;  Alsace  (the  plants 
very  far  apart)  190  ;  Venezuela  (an  ordinary  crop)  238.  Besides 
the  grain  and  the  straw,  the  husks  and  the  cores  of  Indian  corn  are 
all  extremely  valuable  upon  the  farm  as  forage,  and  as  affording 
manure. 

Maize  has  been  analyzed  by  M.  Payen,  and  found  to  contain  i 
starch  71.2;  gluten,  albumen,  &c.,  12.3  ;  fat,  oil,  9.0;  dextrine  and 
glucose  0.4;  woody  tissue  5.9;  and  salts  1.2;  100.0.  T  found 
0.02  of  azote  in  a  sample  of  dry  maize,  which  I  analyzed,  a  quantity 
which  indicates  12.5  of  gluten  and  albumen,  a  result  that  coincides 
exactly  with  M.  Payen's  analysis. 

Rice,  {Oriza  saliva.)  Rice  is  an  aquatic  plant  which  can  only 
be  grown  in  low  moist  lands  that  are  easily  inundated.  The  ground 
is  ploughed  or  stirred  superficially,  and  divided  into  squares  of  from 
twenty  to  thirty  yards  in  the  sides,  separated  from  each  other  by 
dikes  of  earth,  about  two  feet  in  height,  and  sufficiently  broad  for  a 
man  to  walk  upon.  These  dikes  are  for  retaining  the  water  when 
it  is  required,  and  to  permit  of  its  being  drawn  off"  when  the  inunda- 
tion is  no  longer  necessary.  The  ground  prepared,  the  water  is  let 
on,  and  kept  at  a  certain  height  in  the  several  compartments  of  the 
rice-field,  and  the  seedsman  goes  to  work.  The  rice  that  is  to  be 
used  as  seed  must  have  been  kept  in  the  husk  ;  it  is  put  into  a  sack, 

16 


182  COFFEE. 

which  is  immersed  in  water,  until  the  grain  swells  and  shows  signs 
of  germination  ;  the  seedsman  walking  through  the  inundated  fisld, 
scatters  the  seed  with  his  iiand  as  '.'sual,  the  rice  immediately  sink* 
to  the  bottom,  and  may  even  pencorate  to  a  certain  depth  into  the 
mud.  In  Piedmont,  where  the  sowing  takes  place  at  the  beginning 
of  April,  they  generally  use  about  fifty-five  pounds  of  seed  per  acre. 
The  rice  begins  to  show  itself  above  the  surface  of  the  water  at  the 
end  of  a  fortnight ;  as  the  plant  grows,  the  depth  of  the  water  is  in- 
creased, so  that  the  stalks  may  not  bend  with  their  own  weight. 
About  the  middle  of  June  this  disposition  is  no  longer  to  be  appre- 
hended ;  the  rice  is  no  longer  so  flexible  as  it  was,  so  that  the  water 
can  be  drawn  off  for  a  few  days  to  permit  hoeing,  after  which  the 
water  is  let  on  and  maintained  to  the  height  of  the  plant ;  in  July  it 
is  usual  to  top  the  stalks,  an  operation  which  renders  the  flowering 
almost  simultaneous.  Rice  generally  flowers  in  the  beginning  of  the 
month  of  August,  and  a  fortnight  later  the  grain  begins  to  form. 
It  is  at  this  period  especially  that  the  stalks  require  to  be  supported, 
and  this  is  eflfectually  done  by  keeping  the  water  at  about  half  their 
height.  The  rice-field  is  emptied  when  the  straw  turns  yellow. 
The  harvest  generally  takes  place  at  the  end  of  September.  In  the 
Isle  of  France,  rice  is  cultivated  in  very  damp  soils,  upon  which  a 
great  deal  of  rain  falls,  but  which  are  not  flooded  artificially,  I 
have  seen  the  same  process  followed  in  other  tropical  countries 
which  I  have  visited,  but  I  do  not  think  that  the  produce  is  so  great, 
or  the  crop  so  certain,  as  where  inundation  is  employed.  In  Pied- 
mont, the  usual  return  from  a  rice-field  is  reckoned  at  about  50  for  1 
of  seed.  At  Muzo,  in  New  Granada,  the  paddy  fields,  which  are 
not  inundated,  under  the  influence  of  a  mean  temperature  of  26°  cent. 
(79°  Fahr.)  yield  100  for  1. 

Thrqp  kinds  of  rice  yielded,  on  analysis,  the  following  quantities 
of— 

Carolina.  Piedmont.  Rice. 

Starch 89.5  90.1  86.9 

Gluten,  albumen,  &c 3.8  3.9  7.5 

Fattymatters 0.2  0.3  0.8 

Sugar  (glucose ?) 0.3  0.1  >  «. 

Gum 0.7  O.U  •* 

Woody  tissue 5.1  5.1  3.4 

Phosphate  of  lime 0.4  0.4;  «« 

Chloride  of  potassium,  phosphate  of  ditto,  &c.  J      '_ 

100.0  100  U  100.0 

M.  Payen's  analysis  indicates  a  proportion  of  azote,  the  double  of 
that  found  by  M.  Braconnot.  In  a  trial  for  azote,  which  I  made 
myself,  I  found  1.2  of  this  element  per  cent.,  which  would  show  the 
amount  of  albumen  and  gluten  to  be  7.5,  a  quantity  that  corresponds 
exactly  with  M.  Payen's  valuation. 

Coffee,  {Coffea  Arahica.)  The  habit  of  using  the  infusion  of 
coffee  appears  to  have  been  introduced  into  Europe  about  the  middle 
of  the  sixteenth  century.  The  first  public  estabiisfhments  for  the  sale 
of  the  drink  were  opened  in  Constantinople,  in  the  year  1554.  The 
use  of  coffee  remained  for  a  long  time  coniiaed  to  the  East ;  but  b 


COFFEE.  183 

degrees  it  spread,  and  at  the  present  day  the  consumption  of  the  article 
in  Europe  exceeds  660,000,000  of  pounds  annually.  The  greater 
portion  of  coffee  consumed  in  Europe  is  the  produce  of  America,  and 
yet  it  is  not  more  than  a  century  since  it  was  first  grown  in  the  New 
W(.rld. 

The  oofFee-plant  thrives  between  the  tropics  in  situations  where  the 
mean  and  nearly  constant  temperature  is  between  22°  and  26°  C, 
(71.5°  and  80°  F.) 

Coffee  is  rarely  sown  in  a  nursery  :  the  seeds  are  made  to  germinate 
still  surrounded  by  their  natural  pulp,  and  wrapped  up  in  leaves  of  the 
banana.  The  young  plants,  after  seven  or  eight  days  of  germina- 
tion, are  put  into  the  ground.  In  the  valley  d'Aragua  an  acre  of 
ground  of  good  quality  is  generally  laid  out  with  about  1040  plants. 
The  coffee-plant  flourishes  in  the  course  of  the  second  year  ;  when 
left  to  grow  unimpeded  it  will  attain  a  height  of  from  23  to  26  feet, 
but  it  is  seldom  allowed  to  grow  so  high,  its  upward  progress  being 
checked  by  pruning ;  the  planters  of  Venezuela  generally  keep  it  at 
a  height  of  from  five  to  six  feet.  The  shrub  receives  the  care  of 
the  planter  during  the  first  two  years  ;  the  ground  must  be  kept  free 
from  vk^eeds,  and  the  growth  of  parasites  must  above  all  be  prevented. 
To  thrive,  the  coffee-plant  requires  frequent  rains  up  to  the  time  of 
flowering.  The  fruit  bears  a  strong  resemblance  to  a  small  cherry, 
and  is  ripe  when  it  becomes  of  a  red  color,  and  the  pulp  is  soft  and 
very  sweet.  As  the  berries  never  ripen  simultaneously,  the  coffee 
harvest  takes  place  at  different  times,  each  requiring  at  least  three 
visits  made  at  intervals  of  from  five  to  six  days.  A  negro  will 
gather  from  ten  to  twelve  gallons  of  fruit  in  the  course  of  a  day. 

Two  beans  are  found  in  the  interior  of  each  berry  ;  in  order  to 
free  these  from  the  pulp  which  surrounds  them,  they  are  passed 
hrough  a  kind  of  mill,  and  the  coffee  is  steeped  in  water  for  twenty- 
four  hours  in  order  to  free  it  from  the  mucilaginous  matter  which 
adheres  to  it;  it  is  then  dried  by  being  spread  out  upon  a  floor  under 
a  shed.  In  the  coffee  plantations  of  Venezuela  which  I  visited,  I 
saw  them  proceed  in  another  way.  The  berries  were  exposed  to 
the  sun  upon  a  piece  of  ground  somewhat  inclined,  and  spread  out 
to  about  three  inches  in  thickness ;  the  pulp  soon  enters  into  fer- 
mentation, and  a  very  distinct  vinous  odor  is  exhaled,  and  the  juice 
altered  either  flows  away  or  dries  up ;  at  the  end  of  a  fortnight  or 
three  weeks  the  berries  are  all  dry  and  shrivelled,  and  they  then 
undergo  two  triturations,  one  to  obtain  the  seeds  or  beans,  the 
other  to  detach  a  thin  pellicle  which  surrounds  them.  Three  bush- 
els of  berries  will  yield  from  85  to  90  lbs.  of  marketable  coffee. 

During  the  destruction  of  the  sugary  matter  contained  in  the  pulp 
of  the  berry,  a  considerable  quantity  of  spirit  is  produced  and  dissi- 
pated. M.  Humboldt,  struck  with  the  readiness  with  which  the 
berry  of  the  coffee-plant  runs  into  fermentation,  expresses  his  sur- 
prise that  no  one  ever  thought  of  obtaining  alcohol  from  it.  In  an 
old  work,  however,  I  find  the  following  passage  :  "  The  inhabitants 
of  Arabia  take  the  skin  which  surrounds  the  coffee  bean  and  prepare 
it  as  we  do  raisins  ;  they  form  a  drink  with  it  for  refreshment  during 


184  COCOA. 

the  summer."*  This  vinous  liquor  appears  to  enjoy  all  the  exciting 
properties  which  are  esteemed  in  the  infusion  of  coffee. 

The  coffee-plant  continues  to  produce  to  the  age  of  forty  to  forty- 
five  years ;  it  bears  to  a  co.  siderable  extent  even  in  the  third  year. 
Some  siirubs  yield  from  17  :o  22  lbs.  of  dry  coffee  beans ;  but  thia 
is  a  very  large  quantity.  An  acre  of  land  in  the  valley  d'Aragua, 
planted  with  about  1040  shrubs,  will  yield  about  940  or  950  lbs., 
which  is  at  the  rate  of  somewhat  less  than  1  lb.  per  shrub. 

Coffee  contains  the  same  active  principle  as  tea,  coffeine,  but  in 
less  proportion  ;  the  researches  of  different  chemists  have  also 
shown  the  presence  of  a  particular  acid  called  coffeic  acid,  of  fatty 
matters,  a  volatile  oil,  a  coloring  matter,  albumen,  tannin,  and  alka- 
line and  earthy  salts. 

Cocoa,  {Theobroma  cacao.)  The  ancient  Mexicans  cultivated  the 
cocoa-tree,  and  with  its  seeds  prepared  tablets  similar  to  the  choco- 
late of  modern  times.  The  use  of  cocoa  appears  to  have  been  in- 
troduced after  the  conquest  into  the  other  parts  of  the  continent ; 
nevertheless,  the  cocoa-tree  is  indigenous  in  the  hot  and  humid 
forests  of  South  America.  M.  Goudot  discovered  several  species  in 
New  Granada  ;  among  others,  that  which  is  known  at  Muso  under 
the  name  of  the  Cacao  montaraz  :  this  cocoa-tree,  which  attains  a 
height  of  from  25  to  30  feet,  yields  a  considerable  quantity  of  fruit ; 
the  natives  prepare  a  chocolate  from  its  beans,  which  is  extremely 
bitter,  and  which  they  regard  as  an  excellent  febrifuge.  The  wild 
Indians  still  appear  to  be  ignorant  of  the  profit  that  may  be  made  of 
the  seeds  of  the  cocoa-tree  ;  they  only  eat  the  pulp  of  fruit  which 
surrounds  them.  Cocoa  was  introduced  into  Europe  by  the  Span- 
iards, and  in  no  long  space  of  time  this  production  of  the  New 
World  became  the  object  of  a  very  considerable  traffic. 

It  is  a  fact  well  known  to  the  husbandmen  of  tropical  countries, 
that  a  virgin  soil  is  quite  indispensable  to  the  success  of  a  cocoa 
plantation  ;  nothing  but  failure  has  followed  attempts  to  replace  the 
sugar-cane,  indigo,  maize,  &c.,  with  cocoa,  a  plant  which  to  succeed 
requires  a  rich,  deep,  and  moist  soil,  heat  and  shade  ;  nothing  suits 
it  better  than  a  forest  brake,  the  surface  of  which  is  susceptible  of 
irrigation. 

AU  the  important  cocoa  plantations  which  I  visited  had  a  common 
physiognomy  :  they  were  all  situated  in  the  hottest  regions,  at  a 
short  distance  from  the  sea,  near  torrents,  or  on  the  banks  of  great 
rivers.  The  cocoa  husbandry  ceases  to  be  profitable  in  localities 
which  have  not  a  mean  temperature  of  at  least  24°  C,  (75.2°  Fahr.,) 
and  I  have  had  occasion  to  take  part  in  attempts  that  were  as  fruit- 
less as  expensive  to  cultivate  the  cocoa-tree  in  a  brake  where  the 
heat  of  the  climate  from  my  own  observations  did  not  exceed  22.8" 
C.  (73°  Fahr.)  Under  the  influence  of  this  temperature,  the  trees 
presented  a  very  good  appearance ;  in  the  course  of  a  few  years 
liiey  flowered,  but  the  fruit,  which  was  always  small,  rarely  came  to 
uiaturity.     When  a  piece  of  land  has  been  selected  for  a  cocoa 

•  Mem.  of  the  Academy  of  Ii-,9;Tiptions,  vol.  xxiii  p.  214. 


COCOA.  185 

plantation,  they  begin  by  establishing  a  good  system  of  shade.  Oc- 
casionally a  certain  number  of  trees,  with  large  and  leafy  crowns, 
are  left  standing  ;  but  in  general  certain  plants,  which  grow  rapidly, 
are  had  recourse  to  as  a  means  of  procuring  shade.  In  the  neigh- 
borhood of  Caraccas  they  shade  with  the  erylhrina  umbrosa ;  and 
in  some  plantations  they  take  advantage  of  the  shade  of  the  ba- 
nana ;  finally,  the  two  modes  of  procuring  shade  are  frequently  con- 
ioined. 

In  the  province  of  Guayaquil  they  plant  the  beans  of  the  cocoa 
directly.  In  Venezuela  they  prefer  raising  the  plant  in  a  nursery, 
which  is  always  selected  of  the  most  fertile  soil,  and  deeply  trenched. 
The  seeds  are  sown  immediately  before  the  setting  in  of  the  rains, 
and  germination  takes  place  in  from  eight  to  ten  days.  In  a  good 
soil,  at  two  years  of  age  the  cocoa-plant  will  have  attained  a  height 
of  nearly  3  feet ;  it  is  then  pruned  hy  having  two  of  its  upper  branch- 
es removed,  and  is  transplanted.  In  the  upper  valley  of  the  Rio 
Magdalena,  where  there  are  many  valuable  cocoa-groves,  the  sow- 
ing is  performed  in  ground  well  prepared  and  protected  by  screens 
made  with  palm  leaves ;  here  the  young  cocoas  are  transplan!«3d 
when  they  are  six  months  old.  During  the  whole  of  the  time  that 
the  plants  remain  in  this  nursery  they  continue  to  be  well  shaded ; 
and  they  are  watered  once  a  week  by  water  poured  upon  the 
screens. 

The  tree  seldom  comes  into  flower  under  thirty  months  old.  I 
have  known  planters  who  always  destroyed  these  first  flowers,  and 
who  never  suffered  any  fruit  to  ripen  before  the  fourth  year,  and 
that  too  under  the  most  favorable  circumstances  in  regard  to  climate, 
in  situations  where  the  mean  temperature  was  27  5°  C.,  between  81° 
and  82°  Fahr.  In  less  favorable  situations  it  is  necessary  to  wait 
six  or  seven  years  before  gathering  the  first  fruits  of  a  cocoa  planta- 
tion. There  are  few  arborescent  plants  which  have  so  small  a  flower, 
and  especially  a  flower  so  disproportionate  to  the  size  of  its  fruit,  as 
the  cocoa-tree.  The  diameter  of  a  bud,  measured  at  the  moment  of 
its  expansion,  does  not  exceed  4  millimetres — -0.157  of  an  English 
inch.  The  flowers  appear  principally  upon  the  trunk  of  the  tree 
itself;  they  rarely  show  themselves  beyond  the  middle  of  the  larger 
branches  ;  occasionally  they  appear  upon  the  roots  which  happen  to 
be  above  the  ground. 

To  receive  the  young  plants  grown  in  the  nursery,  the  ground 
properly  shaded  is  first  freed  from  weeds.  Trenches  are  then  cut, 
either  to  season  the  ground  or  to  irrigate  it  when  requisite.  The 
young  plants  are  set  in  rows  at  regular  and  considerable  distances, 
which  vary,  however,  with  the  quality  of  the  soil ;  and  the  general 
opinion  is,  that  the  better  the  soil  the  greater  should  be  the  space 
from  tree  to  tree.  Thus  in  the  valley  of  del  Tuy,  in  the  neighbor- 
hood of  Puerto  Cabello,  the  cocoa-trees  are  set  at  the  distance  of 
about  16  feet  apart  in  the  best  soils,  and  at  the  distance  of  about  13 
feet  only  in  soils  of  inferior  quality.  In  the  windward  islands,  where 
the  soil  is  generally  less  fertile  th'an  on  the  continent,  the  trees 
Btand  at  the  distance  of  from  6  or  7  to  9  or  10  feet  apart.     A  reasoo 

16* 


186  COCOA. 

for  this  practice  may  be  readily  assigned  ;  in  the  more  fertile  soils 
the  trees  grow  more  vigorously,  the  branches  spread  further,  and 
consequently  require  a  larger  space. 

Once  the  cocoa-tree  is  in  the  plantation,  it  is  regularly  pruned  to 
prevent  its  branches  becoming  too  numerous.  It  sometimes  happens 
that  the  branches  show  a  tendency  to  bend  down  towards  the  ground, 
in  which  case  they  are  fastened  up  around  the  trunk,  until  they 
acquire  strength  and  a  better  direction.  The  soil  around  the  trunk 
is  hoed  from  lime  to  time  to  the  extent  of  about  a  yard  in  circum- 
ference, and  the  capillary  roots,  which  spring  from  the  base  of  the 
trunk,  are  removed  in  the  course  of  the  operation. 

From  the  fall  of  the  flower  to  the  complete  ripeness  of  the  fruit 
there  elapses  an  interval  of  four  months.  The  fruit  is  of  an  elon- 
gated form,  slightly  bent,  and  terminated  in  a  point ;  its  length  is 
about  9  inches,  and  its  greatest  diameter,  which  is  near  the  point  of 
attachment,  is  from  6  to  7  inches.  Externally,  the  cocoa-nut  pod 
is  furrowed  longitudinally.  Its  color  varies  from  a  greenish  white 
to  a  reddish  violet,  the  latter  being  the  more  common  tint.  Internal- 
ly the  flesh  of  the  fruit  is  generally  white,  although  it  has  sometimes 
a  rose-color  ;  it  is  sweet  and  acid,  and  of  a  very  agreeable  flavor. 
The  seeds  are  generally  twenty-five  in  number  in  each  fruit,  and  at 
first  are  white ;  they  are  oleaginous  and  slightly  bitter ;  in  drying 
they  acquire  a  brown  tint.  The  fruit  is  known  to  be  ripe  by  its 
color,  and  particularly  by  the  ease  with  which  it  is  gathered  from 
the  tree.  There  are  two  grand  cocoa  harvests  in  the  course  of  the 
year,  at  six  months'  interval ;  still,  in  old  and  large  plantations  the 
harvest  is  almost  incessant,  as  it  is  not  uncommon  to  observe,  on  the 
same  cocoa-tree,  ripe  fruits  and  fresh  flowers.  To  obtain  the  seeds 
the  fruit  is  opened  with  a  piece  of  wood,  having  a  rounded  extremity. 
The  produce  is  classed  according  to  its  quality,  care  being  taken  to 
throw  out  all  the  beans  that  are  not  sufficiently  ripe  or  that  are 
damaged  ;  they  are  then  exposed  in  the  sun.  Every  evening  the 
day's  gathering  is  collected  into  a  heap  under  a  shed,  and  a  brisk 
fermentation  is  soon  set  up,  which  would  become  destructive  were  it 
suffered  to  continue.  Next  day  the  heap  is  scattered,  and  the  drying 
goes  on  in  the  sun,  several  days'  exposure  being  required  before  the 
drying  is  complete.  Occasionally  the  drying  is  retarded  and  ren- 
dered difficult  by  the  occurrence  of  rain,  and  there  would  certainly 
be  many  advantages  in  effecting  it  by  the  stove.  It  has  been  found 
that  100  lbs.  of  fresh  beans  give  from  45  to  50  lbs.  of  dry  and  mar- 
ketable cocoa.  In  Venezuela,  a  cocoa-tree  which  is  over  seven  or 
eight  years  old,  will  yield  annually  for  more  than  forty  years  over 
1|  lb.  (1.65  lb.)  of  dry  and  marketable  cocoa.  An  acre  of  ground, 
which  in  good  plantations  will  be  set  with  about  two  hundred  and 
thirty-three  trees,  produces  in  a  middling  year  about  383  lbs.  weight 
The  cocoa-tree  appears  to  yield  most  abundantly  when  it  is  abou 
twelve  years  of  age,  and  its  produce  in  the  fertile  lands  of  Upper 
Magdalena,  according  to  M.  Goudot,  is  greatly  superior  to  what  it 
is  in  Venezuela.     A.t  Gigante,  for  example,  each  adult  tree  yieldi 


PEAS,    BEANS,    ETC. 


187 


4.4  lbs.  of  dry  cocoa  annually,  and  the  produce  of  an  acre  there  may 
be  estimated  at  733  lbs.  'w 

Cocoa  beans  contain  albumen,  a  particular  principle,  tbeobroxnine, 
analogous  to  coffeine,  a  coloring  matter,  and  a  large  quantity  of  oil  or 
fat,  which,  from  experiments  made  in  my  laboratory,  appears  to 
amount  to  43  per  cent.  The  presence  of  a  large  quantity  of  albu- 
men and  fatty  matter  in  cocoa  explains  its  highly  nutritious  qualities. 
It  is  indeed  one  of  the  most  wholesome  and  restorative  articies  of 
sustenance  known.  Nevertheless,  very  opposite  statements  have 
been  made  upon  the  virtues  of  cocoa  or  chocolate,  of  which  the  bean 
forms  the  basis.  Benzoni,  in  his  History  ot  the  New  World,  de- 
clared chocolate  to  be  a  drink  that  was  fitter  for  hogs  than  men ; 
and  Father  Acosta  declares  the  taste  for  cocoa  to  be  unreasonable. 
On  the  other  hand,  Fernando  Cortez  and  one  of  his  gentlemen  fol- 
lowers are  perhaps  guilty  of  exaggeration  when  they  say,  "  that  he 
who  has  taken  a  cup  of  chocolate  may  march  the  rest  of  the  day 
without  other  aliment  I"*  Without  going  the  whole  of  this  length 
with  Cortez,  1  still  allow  that  chocolate  is  one  of  the  best  articles 
for  travelling  upon,  especially  in  the  uninhabited  forests  of  South 
America,  where  it  is  a  matter  of  the  highest  moment  to  have  the 
bulk  and  the  weight  of  necessary  rations  as  small  as  possible. 

Seeds  of  leguminous  plants.  The  leguminous  plants  that  are  cul- 
tivated as  food  for  man  are  beans,  peas,  haricots,  and  lentils;  vetches 
are  grown  exclusively  for  the  use  of  cattle. 

Leguminous  plants  scarcely  ever  open  rotations ;  but  they  very 
often  wind  them  up.  Speaking  generally,  however,  they  may  follow 
any  crop.  In  speaking  of  the  Indian  corn,  I  have  said  that  haricots 
and  beans  might  be  advantageously  intercalated. 

The  meteorological  observations  I  have  made  in  different  coun- 
tries lead  me  to  conclude  that  to  succeed,  leguminous  plants  require 
a  temperature  which  in  the  mean  does  not  fall  below  from  14°  to  15° 
C,  (57°  to  59°  F.)  Hot  climates  agree  with  them  perfectly  ;  I  have 
followed  them  from  the  sea-board  of  the  equatorial  Andes  to  a  height 
of  from  8-200  to  9800  feet  above  the  level  of  the  sea.  Schwertz  has 
given  the  following  statement  of  the  produce  of  the  different  legu- 
minous plants  generally  cultivated : 


Plants. 

Weight  per 

Produce  per  acre 

Weight  of  dry  straw 

bushel  in  lbs. 

in  bushels. 

or  haulm  per  acre. 

Tons.  Cvvts.     qrs.       lbs. 

Haricots      .     . 

47.5 

66.7 

Beans     .     .     . 

65.5 

66.2 

2        2        2        17 

Peas       .     .     . 

57.9 

38.5 

2        4        2        11 

Lentils    .     .     . 

62.3 

39.8 

Vetches  .    .     . 

62.3 

41.2 

2        4        2        11 

The  analyses  we  have  of  leguminous  vegetables  show  the  follow 
ing  proportic  n  of  elements  : 


*  Humboldt,  Travels,  vol.  v.  p. 


iS8 


THE  HOP. 


« 

Haricots 

Peas. 

Lentils. 

Legumine 

22.0 

20.4 

22.0 

Starch  .... 

41.0 

47.0 

40.0 

Fatty  matters 

3.0 

2.0 

2.5 

Sugar  (glucose  ?)  . 

0.3 

2.0 

1.5 

Gum      .... 

4.0 

5.0 

7.0 

Woody  fibre,  pectic  acid 

8.0 

11.0 

12.0 

Salts,  phosphates,  &c. 

3.2 

3.0 

2.5 

Water  and  loss 

17.5 

9.6 

12.5 

100.0 

100.0 

100.0 

Besides  these  principles,  a  quantity  of  tannin  has  always  been 
found  in  the  skin  of  the  seed  of  all  leguminous  plants. 

The  Hop,  {Humulus  lupulus.)  From  its  very  general  use  in 
making  beer,  the  hop  has  become  an  object  of  great  importance, 
both  in  an  agricultural  and  commercial  point  of  view. 

The  hop  may  be  cultivated  in  any  soil  that  is  of  sufficient  depth 
and  fertility  ;  it  thrives  especially  in  rich  and  turfy  loams,  such  as 
those  of  Haguenau,  where  there  are  many  beautiful,  hop-gardens. 
The  plant  is  propagated  in  the  spring  by  setting  the  sprouts  or  radicu- 
lar buds  in  ground  trenched  to  the  depth  of  18  inches  at  least,  at  in- 
tervals of  about  a  couple  of  yards  from  one  another.  Within  a  few 
weeks  the  young  hop-plant  is  growing  lustily;  and  as  it  is  a  climber, 
it  is  trained  upon  a  pole  of  from  12  to  20  feet  in  height.  The  ground 
is  usually  hoed  towards  the  end  of  June.  The  first  crop  from  a  new 
plantation  is  always  trifling  in  amount ;  the  ground  is  then  manured. 
The  following  spring  all  the  eyes  or  buds  that  have  become  devel- 
oped near  the  root  are  removed,  except  six  or  seven,  which  are  left 
to  slw»ot.  The  hop  harvest  generally  occurs  about  the  middle  of 
September  :  the  poles  are  pulled  up,  the  stems  are  cut,  and  the 
strobiles  are  picked  off  into  baskets  by  hand,  and  immediately  car- 
ried to  the  stove  or  kiln,  where  they  are  dried  with  a  very  gentle 
heat,  in  order  not  to  dissipate  their  fine  aromatic  particles. 

A  hop-garden  produces  very  variously  in  different  countries  and 
districts,  and  in  different  years.  The  produce  of  an  acre  in  hopf 
has  been  stated  to  be  : 

In  Flanders, 13  cwt 

Germany  (mean  of  10  years,)  .         .         10     " 

France  (near  Paris,)  .         .         .         10     " 

"      (Roville,  mean  of  10  years,)  1\  " 

[England,  from  9  to  10,  and  from  12  to  14  cwt.] 

The  strobiles  of  the  hop  are  covered  with  a  yellow  pulverulen* 
substance,  which  has  been  held  to  furnish  in  principal  part  the  ex 
tractive  matter  that  is  so  valuable  in  brewing.  To  procure  this  sub 
stance  it  is  enough  to  sift  a  quantity  of  hops  after  they  have  beer 
dried  by  a  gentle  heat.  This  yellow  powder,  which  appears  to  b« 
the  useful  principU;  in  the  hop,  and  consequently  gives  it  its  value 


BANANA. 


189 


is  not  found  in  the  same  proportion  in  the  produce  of  all  hop-gardens. 
This  clearly  appears  from  the  inquiries  of  Messrs.  Payen  and  Cheva- 
lier. They  found,  for  example,  that  while  100  parts  of  thd  hops  of 
Belgium  contained  18  of  yellow  substance  and  70  of  mere  leaf, 
those  of  England  contained  no  more  than  10  of  yellow  ir.atler  and 
87  of  leaf,  and  those  of  Germany  the  still  smaller  quantity  of  8  of 
yellow  matter  to  88  of  leaf.  This  yellow  pulverulent  matter  con- 
tains wax,  resin,  gum,  a  bitter  principle,  certain  azotized  principles, 
a  volatile  oil,  and  salts,  among  others  acetate  of  ammonia. 


FLESHY  OR  PULPY  FRUITS. 

The  fleshy  fruits  almost  all  contain  the  same  principles,  but  in 
very  different  proportions.  It  is  consequently  the  predominating 
piinciple  which  in  some  sort  characterizes  each  variety,  that  gives 
it  its  flavor,  odor,  &c.  :  sugar,  albumen,  gum,  starch,  acids,  fixed 
oils,  essential  oils,  woody  fibre,  are  almost  invariably  found  secreted 
in  their  pulps,  with  a  larger  or  smaller  quantity  of  water.  An  in- 
genious classification  of  fruits  has  been  formed  on  the  basis  of  the 
predominance  of  the  different  substances  which  have  just  been  enu- 
merated :  thus  those  fruits  in  which  the  starchy  principle  predomi- 
nates are  feculent  or  amylaceous  fruits ;  those  in  which  the  sugar 
predominates  are  saccharine  fruits,  and  so  on. 

M.  Berard  has  analyzed  a  great  number  of  fruits  in  the  course  of 
his  researches  on  their  ripening.*  It  is  proper  to  say,  however,  that 
some  of  the  principles  brought  to  light  by  modern  analysis  do  not 
figure  in  M.  Berard's  list  of  elements ;  among  the  number,  pectic 
acid,  gallic  acid,  small  quantities  of  volatile  oils,  and  of  salts  of 
potash  formed  by  vegetable  acids. 


. 

i 

1 

s 

h 

.« 

t 

i: 

s 

a  0 

i 

V 

0) 

Albumen  and  gluten 

< 

Pk 

^ 

o 

o 

Pu. 

0.2 

0.9 

0.9 

0.6 

0.3 

0.2 

Coloring  matter 

0.1 

0.1 

Vegetable  tissue 

1.9 

1.2 

8.0 

1.1 

1.1 

2.2 

Cum 

5.1 

4.9 

0.8 

3.2 

2.1 

2.1 

Sugar 

16.5 

li.6 

6.0 

18.1 

24.8 

11.5 

Malic  acid 

1.80 

1.1 

2.4 

2.0 

0.6 

0.1 

Citric  acid 

(( 

0.3 

Lime 

0.1 

0.3 

0.1 

Water       . 

J4.4 

80.2 

81.3 

74.9 

71-0 

83.9 

100.00 

100.0 

100.0 

lOU.O 

100.0 

100.0 

Banana.  Of  all  the  pulpy  fruits,  the  banana  is  that  perhaps  whicli 
IB  most  extensively  used  as  food  by  man.    It  is  the  usual  nourish 


♦  Ann.  de  Chimie,  t.  xvi.  p.  225,  2d  series 


190  BANANA. 

ment  of  the  inhabitants  of  most  of  the  countries  between  the  tropics, 
where  its  cultivation  is  as  important  as  that  of  the  cereals  and  fari- 
naceous roots  in  the  temperate  zone.  The  ease  with  which  it  is  cul- 
tivated, the  small  space  of  ground  it  occupies,  the  certainty,  the 
abundance,  and  the  continuance  of  its  produce,  the  diversity  of  food 
it  yields  according  to  the  degree  of  maturity,  make  the  banana  an 
object  of  admiration  to  the  European  traveller.  In  climates  where 
man  scarcely  feels  the  necessity  of  clothing  himself,  or  of  raising  a 
shed  for  his  protection,  he  is  seen  gathering  almost  without  labor 
supplies  of  food  as  abundant  as  they  are  wholesome  and  varied  from 
the  banana-tree.  It  is  the  banana  which  has  given  rise  to  that  prov- 
erb so  consoling  and  so  true,  which  is  frequently  heard  between  the 
tropics,  viz.  "  No  one  dies  of  hunger  in  America;"  he  who  is  hun- 
gry will  be  welcomed  and  fed  in  the  very  poorest  cabin.  Botanists 
distinguish  three  principal- varieties  of  the  banana:  1st.  the  Musa 
paradisica;  2d.  the  Musa  sapientium  ;  3d.  the  Musa  regia. 

The  American  origin  of  the  banana  has  been  called  in  question. 
Oviedo  in  his  natural  history  of  the  Indies  affirms  that  it  was  brought 
from  the  Canary  Isles  to  St.  Domingo  by  a  monk.  Foster  adopted 
this  opinion,  which  is  corroborated,  says  M.  de  Humboldt,  by  the 
complete  silence  of  the  first  travellers  who  visited  the  New  World 
in  regard  to  it.  Nevertheless,  the  testimony  of  the  Inca  Garcilasso  de 
la  Vega  proves  obviously  that  the  banana  flourished  in  America  be- 
fore the  arrival  of  the  Spaniards ;  in  his  royal  commentaries  he 
speaks  of  the  banana  as  constituting  the  chief  food  of  the  Indians  in 
the  warmest  parts  of  Peru. 

The  banana  is  everywhere  cultivated  in  the  neighborhood  of  the 
equator,  in  situations  at  no  great  height  above  the  level  of  the  sea. 
The  cultivation  is  most  profitable,  the  crop  is  most  abundant,  and  at- 
tains maturity  in  the  shortest  space  of  time  in  low  lying  districts 
where  the  mean  temperature  is  from  24°  to  27.5°  C,  (75.5°  to  82* 
F.)  Some  estimate  may  be  formed  of  this  from  the  low  price  of  the 
banana  in  such  districts ;  upon  the  borders  of  the  great  river  de  la 
Magdalena,  I  gave  one  franc  or  about  lOd.  for  about  220  lbs.  weight 
of  the  fruit.  The  day's  wages  of  a  man  being  generally  about  Is.  8d., 
it  is  beyond  all  doubt  the  cheapest  food  that  can  be  had  in  the  world. 

In  looking  at  the  cultivation  of  the  banana  at  different  heights  in 
the  equatorial  Cordilleras,  I  arrived  at  the  following  conclusions : 

Temperature  28°  C.  (between  82°  and  83°  F.)  the  cultivation  ex- 
tremely advantageous ;  at  24°  C.  (between  75°  and  76°  F.)  the  cul- 
tivation advantageous  ;  at  22°  (71°  and  72°  F.)  the  cultivation  mid- 
dling ;  at  19°  C.  (or  between  66°  and  67°  F.)  the  cultivation  disad- 
vantageous. 

The  banana  is  propagated  by  means  of  suckers  or  offsets.  It  re- 
quires a  rich  and  humid  but  well-drained  soil,  the  plantation^  being 
arranged  a  little  before  the  setimg  m  ot  the  rains.  The  earth  is 
freed  from  weeds,  and  dug  either  entirely  or  more  generally  only  at 
regular  distances  here  and  there,  where  it  is  proposed  to  set  the  new 
plant,  a  space  of  6  feet  at  least  being  left  between  each.  The  plant 
lbr9W8  up  several  shoots,  generally  6  or  7,  each  of  which  will  be  dji- 


I 


BANANA.  101 

iowed  to  grow  and  to  carry  fruit ;  when  a  greater  number  make  theit 
appearance,  some  of  them  are  cut  away.  The  time  which  passes  be- 
tween planting  the  slip  and  gathering  the  fruit  varies  according  to 
the  situation ;  in  the  hottest  districts  near  the  level  of  the  sea  ihe 
banana  comes  into  flower  about  nine  months  after  it  has  been  plant- 
ed ;  and  in  three  months  more  the  fruit  has  formed  and  become  ripe. 
In  cold  situations  an  interval  of  four  months  will  elapse  between  the 
flowering  and  the  ripening  of  the  fruit.  The  care  required  by  a  ba- 
nana plantation  is  not  very  great,  the  principal  duty  being  to  hoe 
around  the  young  plants.  As  the  banana  is  renewed  by  stems  which 
arise  continually  from  the  neck  of  the  root,  it  is  easily  understood 
that  the  plant  will  go  on  yielding  fruit  for  an  indefinite  length  of 
time ;  when  the  fructification  is  complete  in  one  stem,  the  leaves, 
&c.,  wither  and  fall,  and  give  place  to  a  new  stem.  It  is  thus  that 
the  gatherings  from  the  banana  go  on  successively  at  short  intervals, 
and  that  the  same  plant  presents  at  one  and  the  same  moment  fruit 
that  is  ripe,  fruit  that  is  half  ripe,  fruit  that  is  beginning  to  be  formed 
flowers,  and  finally  young  stems,  which  are  rising  as  preparations  for 
the  future.  Thus  no  crop  is  more  assuring  to  the  planter  than  the 
banana.  Climatic  circumstances  may  sometimes  delay,  but  can  never 
destroy  the  hopes  of  the  husbandman.  The  extraordinary  droughts 
which  under  the  burning  climates  of  the  equator  so  frequently  interrupt 
or  destroy  ordinary  herbaceous  plants,  rarely  exert  any  pernicious 
influence  upon  the  banana  plantation,  the  thick  shade  of  which  pre- 
sents a  constant  obstacle  to  the  evaporation  of  moisture.  During 
the  dry  season,  when  for  whole  months  the  heavens  preserve  their 
purity,  and  no  drop  of  rain  falls  to  refresh  the  earth,  the  soil  which 
surrounds  the  banana  still  continues  moist.  It  looks  every  morning 
as  it  it  had  been  watered  during  the  night;  this  salutary  effe  t  is 
produced  by  the  nocturnal  radiation  of  the  leaves  into  the  clear  sky. 
These  leaves,  whose  extent  of  surface  is  considerable,  always  fall 
several  degrees  below  the  temperature  of  the  surrounding  air,  and 
hus  condense  the  watery  vapor  contained  in  the  atmosphere,  which 
drips  down  to  the  foot  of  the  plant. 

The  produce  of  a  banana  plantation  depends  first  upon  the  dis- 
tance at  which  the  bananas  are  placed,  and  next  upon  the  climate. 
It  is  generally  estimated  in  the  very  warm  climates,  that  a  crop  of 
bananas  will  weigh  about  44  lbs.,  and  that  from  an  adult  plant  three 
crops  will  be  obtained  in  the  course  of  a  year.  In  temperate  coun- 
tries, and  towards  the  superior  limits  of  the  banana  plant,  they  do 
not  reckon  on  more  than  two  crops.  According  to  M.  de  Humboldt, 
the  produce  per  acre,  in  hot  countries  where  the  mean  temperature 
is  about  82°  Fahr.,  will  amount  to  75  tons,  8  cwt.  1  qr.  17  lbs.  ;  at 
Cauca,  where  the  temperature  is  about  79"  Fahr.,  the  produce  amounts 
to  ei'tons,  8  cwt.  0  qr,  2  lbs.  ;  at  Ibague,  where  the  temperature  is 
not  higher  than  about  72°,  the  produce,  according  to  M.  Goudot's  es- 
timate, is  26  tons,  17  cwt.  3  qrs.  2  lbs.  The  pulp  of  the  banana  is 
surrounded  by  a  pod  or  husk  of  some  thickness,  which  is  easily  de- 
tached, and  of  which  account  must  be  taken  if  we  would  estimate 
the  actual  weight  of  the  truly  alimentary  matter  afforded.     In  a 


192  BANANA. 

general  way,  and  when  the  banana  is  ripe,  the  shell  may  be  estimated 
at  about  36.8,  the  edible  banana  at  73.2  per  cent. 

The  Musa  paradisica  is  the  variety  of  banana  generally  culti- 
vated, and  it  also  yields  the  heaviest  crops.  The  fruit  of  the  other 
two  varieties  mentioned  is  much  smaller  ;  but  it  is  of  a  much  more 
delicate  flavor.  The  ripe  fruit  of  the  banana  is  of  the  consistence 
of  a  pear  ;  it  is  very  sweet,  and  slightly  acid.  In  the  common  va- 
riety, 1  found  crystallizable  sugar,  gum,  an  acid,  (probably  the  rnalic,) 
gallic  acid,  albumen,  pectic  acid,  woody  fibre,  and  alkaline  and  earthy 
salts.  Dried  in  the  sun,  1000  parts  of  ripe  banana  were  reduced  to 
439  parts  ;  so  that  they  contained  561  parts  of  water.  The  green 
or  unripe  banana  has  a  white  and  almost  insipid  flesh.  In  this  state 
it  scarcely  contaias  any  sugar  ;  it  is  starch  that  predominates.  In 
this  state,  therefore,  it  is  made  a  substitute  for  bread,  for  the  potato, 
or  Indian  corn ;  it  may  be  considered  a  farinaceous  vegetable. 
After  having  removed  the  rind,  the  banana  is  dressed  by  being 
roasted  under  the  ashes  until  the  outer  part  is  slightly  brown  ;  it  is 
then  served  up  at  table,  and  constitutes  a  kind  of  soft  bread,  very 
agreeable  to  the  palate,  and  greatly  preferable,  in  my  opinion,  to  the 
produce  so  much  vaunted  of  the  bread-fruit  tree.  In  the  expeditions 
which  are  undertaken  into  the  forest,  and  when  the  habitations  of 
man  are  to  be  quitted  for  some  considerable  time,  the  green  banana 
is  always  made  a  principal  part  of  the  provision ;  but  then  it  is  pre- 
viously dried,  first  to  lessen  its  weight,  and  then  to  destroy  its  vi- 
tality so  far  as  to  prevent  its  ripening.  This  drying  is  performed  in  a 
baker's  oven,  into  which  the  green  bananas,  stripped  of  their  husks, 
are  introduced,  and  where  they  are  kept  for  about  eight  hours.  On 
being  taken  out,  the  bananas  are  hard,  brittle,  translucent,  and  pre- 
sent the  appearance  of  horn ;  100  lbs.  of  the  green  fruit  give  but  40 
of  dry  substance.  The  banana  thus  prepared  is  called^,  and  will 
keep  for  a  great  length  of  time  without  change.  To  prepare  it  for 
food,  it  is  put  to  steep  in  water,  and  then  boiled  ;  by  adding  a  little 
salted  meat,  a  very  substantial  and  nutritious  meal  is  prepared.  I 
once  made  a  voyage  on  the  Pacific,  in  a  vessel  which  was  princi- 
pally victualled  with  dried  bananas,  which  were  served  out  to  the 
company  like  biscuit. 

When  ripe,,  the  banana  is  no  longer  farinaceous  ;  as  it  ripens,  its 
starch  is  changed  into  gum  and  sugar,  and  an  acid  is  developed. 
But  between  the  farinaceous  and  the  sugary  or  perfectly  ripe  state, 
there  is  one  intermediate,  in  which  it  is  generally  eaten.  Roasted  in 
the  ashes,  the  banana  has  then  a  taste  which  brings  to  mind  that  of 
.he  chestnut ;  it  is  also  eaten  as  a  vegetable,  boiled  in  the  usual  way 
m  water.  Completely  ripe,  the  fruit  is  eaten  raw  or  dressed,  it  is 
then  extremely  sweet ;  a  very  common  practice  is  to  fry  it,  cut  in 
slices,  in  grease. 

I  have  no  data  upon  which  to  estimate  the  nutritive  value  of  the 
banana,  still  I  have  reasons  for  believing  that  it  is  more  nutritious 
than  the  potato.  I  have  seen  men  do  a  great  deal  of  hard  labor  upon 
an  allowance  of  about  6^  pounds  of  half-ripe  bananas,  and  two  ounces 
of  salted  meated  per  diem 


193 


CHAPTER  III. 

or  THE    SACCHARINE   FRUITS,   JUICES,   AND    INFUSIONS   USED   IN   THB 
PREPARATION    OF    FERMENTED    AND    SPIRITUOUS    LIQUORS. 

The  juice  of  all  the  sweet  fruits  when  expressed  and  left  to 
itself  under  the  influence  of  a  suitable  temperature,  presents  the  re- 
markable phenomenon  of  fermentation,  in  the  course  of  which  the 
sugar  disappears  completely,  and  is  replaced  by  alcohol,  the  change 
from  first  to  last  being  accompanied  by  the  disengagement  of  car- 
bonic acid  gas. 

Sugar  alone  does  not  suffice  to  cause  the  vegetable  juices,  which 
contain  it,  to  ferment :  for  example,  a  solution  of  pure  sugar  in  dis- 
tilled water  will  remain  for  a  very  great  length  of  time  without  suf- 
fering the  least  change  ;  exposed  to  the  open  air  it  would  evaporate, 
and  the  saccharine  matter  would  be  found  in  the  same  state  as  it 
was  before  solution  If,  however,  a  small  quantity  of  that  azotized 
principle  which  we  have  called  albumen,  gluten,  &c.,  be  introduced 
into  the  solution,  fermentation  will  speedily  be  set  up,  and  will  run 
through  its  usual  course ;  it  would,  therefore,  appear  to  be  upon  this 
principle  that  the  commencement  and  continuance  of  fermentation 
depends  Fermentation  is  not  set  up  immediately  in  the  juice  of 
fruits ;  a  certain  time  longer  or  shorter  always  elapses  before  it  is 
manifested  ;  the  reason  of  this  is,  that  the  albumen  or  gluten  which 
always  enters  into  the  constitution  of  these  juices,  must  itself  have 
undergone  a  certain  change  in  order  to  act  as  a  ferment.  The  proof 
of  this  is  comprised  in  the  fact  that  all  vinous  liquors  contain  a  very 
small  but  constant  quantity  of  carbonate  of  ammonia,  as  was  shown 
by  M.  Doebereiner.  These  azotized  principles,  which  in  the  fresh 
state  remain  without  action  upon  sweet  juices,  act  immediately  as 
powerful  ferments  when  they  are  employed  after  having  been  ex- 
posed for  some  days  to  the  contact  of  air  and  moisture  ;  after,  in  a 
word,  they  have  themselves  begun  to  suffer  change.  The  quantity 
of  ferment  used  up  or  consumed  in  exciting  and  maintaining  the  fer- 
mentation of  saccharine  juices  is  so  small,  that  we  are  led  to  believe 
that  it  really  acts  by  its  presence  or  contact  alone.  This  view  ap- 
pears the  more  likely,  when  we  know  that,  after  having  added  an 
azotized  substance  to  induce  fermentation  rapidly  in  a  liquid  which, 
besides  sugar,  contains  albumen,  we  find  from  six  to  eight  times  the 
quantity  of  ferment  after  the  phenomena  have  ceased,  which  had 
been  added  in  the  first  instance  ;  that  is  to  say,  we  find  the  whole, 
or  almost  the  whole,  of  the  original  ferment,  and,  in  addition,  that 
which  has  been  produced  by  the  azotized  principles  pre-existing  in 
the  matter  subjected  to  fermentation  ;  this  fact  is  seen  every  day  in 
the  process  of  making  beer. 

The  ferment  or  yeast  thus  produced  is  but  little  soluble  in  water, 
and  in  composition  bears  a  remarkable  affinity  to  the  azotized  mat- 

17 


194  THE  VINOUS    FERMENTATION. 

lers  from  whicl  is  derived  ;  M.  Dumas  has  in  fact  found  it  tot« 
composed  of: 

Carbon 50.6 

Hydrogen 7.3 

Azote 15.0 

Oxygen        ) 

Sulphur       V  27.1 

Phosphorus  ) 

100.0 

Under  the  influence  of  ferment,  sugar  becomes  entirely  cimnged 
into  alcohol  and  carbonic  acid.  The  composition  of  grape-sugar— 
■^^hich  appears  to  be  the  only  one  that  is  susceptible  of  fermentation, 
for  cane-sugar  before  undergoing  this  process  passes  into  the  state 
of  grape-sugar,  as  was  demonstrated  by  M.  Henry  Rose — the  com- 
position of  grape-sugar  is  as  follows  : 

Carbon 36.4 

Hydrogen 7.0 

Oxygen .56.6 

100.0 

and  the  constitution  of  the  substances  which  are  produced  in  the 
process  of  fermentation,  viz.  alcohol  and  carbonic  acid,  being  as 
under : 

Anhydrous  alcohol.  Carbonic  acid.  Water. 

Carbon 52.19  27.27 

Hydrogen 13.02  "  11.1 

Oxygen .34.79  72.73  88.9 

100.0  100.0  100.0 

It  appears  that  the  composition  of  100  parts  of  grape-sugar  may  be 
expressed  by  : 

Carbon.  Hydrogen.  Oxygen, 

Alcohol 46.16  containing  24.24               6.05  16.17 

Carbonic  acid 44.45          "          11.12                 "  32.33 

Water 9.09          "             "                  1.01  8.08 

100.00                      36.36               7M  58!58 

oy  which  it  would  appear  that  during  the  transformation  of  hydrated 
grape-sugar  into  alcohol  and  carbonic  acid,  the  combined  water  is 
set  at  liberty. 

The  first  fermented  vegetable  juice  of  which  I  shall  speak  is 
cane-wine^  or  guarapo  of  the  South  Americans,  a  drink  which  is  m 
common  use  wherever  the  sugar-cane  is  cultivated.  It  is  prepared 
from  the  juice  of  the  sugar-cane  suffered  to  run  into  fermentation. 

The  chicha  of  South  America  is  a  fermented  liquor  prepared  from 
Indian  corn,  and  constitutes  the  wine  of  the  Cordilleras.  The  grain 
is  steeped  for  six  or  eight  hours  in  water,  bruised  upon  a  stone  and 
boiled  ;  the  pulp  which  results  is  then  diffused  through  4|  times  its 
volume  of  water,  and  the  temperature  being  from  60°  to' 65°  F.,  a 
violent  fermentation  is  §oon  set  up  in  the  fluid,  which  begins  to  sub- 
side after  a  period  of  twenty-four  hours,  when  the  chicha  is  potable 
and  now  constitutes  a  liquor  of  an  agreeable  and  decidedly  vinous 
flavor,  in  high  repute  with  those  who  have  acquired  a  taste  for  it 
although  its  muddy  appearance  and  the  sediment  which  it  alware 


CIDER   AND   PERRY WINES.  195 

fits  fall  in  the  vessel  into  which  it  is  received,  render  it  somewhat 
unpleasant  at  first  to  European  eyes.  The  Indians,  however,  always 
drink  it  in  the  muddy  state,  and  even  shake  the  cask  before  turning- 
the  tap.  The  truth  is,  that  chicha  is  at  once  a  drink  and  a  very  nu- 
tritious fqod. 

Guarazo  is  another  vinous  liquor  which  the  Indians. prepare  with 
rice  much  in  the  same  manner  as  they  proceed  with  Indian  corn. 

Cider  and  Perry.  In  countries  where  the  vine  is  not  cultivated, 
a  substitute  for  wine  is  found  in  the  fermented  juice  of  a  variety  of 
sweet  pulpy  fruits,  more  particularly  of  apples  arid  pears.  Of  the 
numerous  varieties  of  apples  which  are  grown  in  cider  countries,  the 
preference  is  generally  given  to  one  which  has  a  rough  and  some- 
what bitter  taste.  The  fruit  is  gathered  by  shaking  or  beating  the 
trees,  and  the  few  that  remain  are  taken  off  by  the  hand  ;  the  fruit 
is  piled  up  in  large  backs  placed  in  cellars.  It  is  crushed  about  two 
months  after  it  is  gathered,  and  the  pulp  is  left  for  ten  or  twelve 
hours  to  macerate  in  the  juice,  in  order  to  give  the  rusty  or  yellow 
color  which  is  esteemed  in  cider.  The  pulp  is  pressed  and  the  juice 
is  run  into  large  vats  or  tuns,  in  which  it  undergoes  fermentation, 
which  having  gone  on  for  about  a  month,  the  temperature  being 
from  55°  to  58°  F.,  the  liquor  is  racked  off  into  smaller  vessels,  in 
which  the  fermentation  goes  on  slowly,  and  the  cider  is  preserved. 
The  fermentation  of  cider  is,  or  always  ought  to  be,  slow ;  still,  with 
time,  the  whole  of  the  sugar  is  transformed  into  alcohol,  if  the  pro- 
cess be  not  interfered  with. 

Wine.  Grape-juice  contains — 1st.  grape-sugar  ;  2d.  albumen  and 
gluten  ;  3d.  pectine  ;  4th.  a  gummy  matter;  5th.  a  coloring  matter  ; 
6th.  tannin  ;  7th.  bitartrate  of  potash ;  8th.  a  fragrant  volatile  oil, 
or  cream  of  tartar  ;  9th.  water.  It  is  obvious,  therefore,  that  grape- 
juice  contains  within  itself  the  elements  necessary  for  the  produc 
tion  of  the  vinous  fermentation.  The  relative  proportions  of  these 
different  elements,  however,  are  singularly  modified  according  to  the 
nature  of  the  vine,  the  quality  of  the  soil,  and  especially  the  heat 
of  the  climate.  There  are  indeed  few  crops  that  are  so  much  at 
the  mercy  of  the  atmosphere  as  that  of  the  vine ;  even  in  the  vine- 
yards that  are  most  favorably  situated,  it  is  rare  that  wines  of  equal 
quality  and  flavor  are  produced  in  two  consecutive  years ;  and  in 
districts  upon  the  verge  of  the  productive  limits  of  the  vine,  under 
what  may  be  called  extreme  climates,  where  the  vine  only  exists  in 
virtue  of  hot  summers,  its  produce  is  still  more  variable,  more  in- 
constant. The  limits  to  the  culture  of  the  vine  in  Europe  are 
generally  fixed  where  the  mean  temperature  is  from  10°  to  11°  C, 
(50°  to  52°  F.  ;)  under  a  colder  climate  no  drinkable  wine  is  pro- 
duced. To  this  meteorological  datum  must  be  added  the  further 
fact  that  the  mean  heat  of  the  cycle  of  vegetation  of  the  vine  must 
be  at  least  15°  C.  (59°  F.,)  and  that  of  the  summer  from  18°  to  19" 
C,  (from  65°  to  67°  F.)  Any  country  which  has  not  these  climatic 
conditions  cannot  have  other  than  indifferent  vineyards,  even  when 
its  mean  annual  temperature  is  above  what  I  have  indicated.  It 
is  impossible,  for  instance,  to  cultivate  the  vine  upon  the  temperate 


196  WINE. 

table-lands  of  South  America,  where  they  neverthelejo  enjoy  a 
mean  temperature  of  from  17°  to  19°  C,  (about  62.6°  to  66.2°  F.,) 
because  that  which  characterizes  the  climate  of  these  elevated 
equinoxial  countries  is  the  constancy  of  the  temperature  ;  the  vine 
grows,  flourishes,  but  the  grapes  never  become  thoroughly  ripe.  In 
these  equatorial  countries  good  wine  cannot  be  made  where  the  con- 
stant temperature  is  not  at  least  20°  C,  (or  68°  F.) 

In  France  the  vine  begins  to  sprout  towards  the  end  of  March, 
and  the  vintage  generally  occurs  in  the  course  of  October.  As  the 
quality  of  wine  depends  mainly  on  the  ripeness  of  the  grapes,  of 
course  the  vintage  does  not  take  place  until  this  is  complete,  or  until 
there  is  no  longer  any  prospect  of  improvement. 

The  must  of  the  grape  is  procured  by  treading  and  pressing  the 
fruit ;  the  juice  is  run  into  vats,  and  the  fermentation  takes  place  in 
cellars  ;  different  procedures,  however,  are  foUowed  in  different 
places.  The  fermentation  having  subsided  in  the  larger  vessels,  the 
wine  is  drawn  off  into  smaller  casks,  which  are  carefully  filled  up 
from  time  to  time,  and  in  which  it  is  preserved. 

Wine  may  be  defective,  especially  by  wanting  strength  and  being 
too  acid.  Sharp  wine  contains  an  excess  of  cream  of  tartar  and 
free  vegetable  acids,  and  is  always  the  produce  of  grapes  which 
have  not  been  completely  ripe.  The  deficiency  of  strength  is  due 
to  the  same  cause  ;  for  it  is  well  known  that  as  the  grape  ripens  its 
acids  disappear  and  are  replaced  by  sugar.  This  deficiency  of  sac- 
charine matter  in  the  must,  is  now  habitually  supplied  by  the  addition 
of  a  quantity  of  artificial  grape-sugar,  prepared  from  starch.  In 
warm  countries,  where  the  grape  always  ripens,  the  quantity  of  tar- 
tar is  small ;  the  sugar  then  predominates  greatly,  sometimes  to  such 
an  extent  that  the  azotized  substance  of  the  must  is  insufficient  as  a 
ferment,  and  it  is  then  that  we  have  wines  of  too  sweet  a  flavor, 
such  as  those  of  Lunel  and  of  Frontignac.  When  these  musts, 
which  are  so  rich  in  sugar,  contain  the  proper  quantity  of  ferment 
they  produce  very  strong  wines,  in  which,  of  course,  the  sweet 
flavor  no  longer  predominates;  such  are  the  dry  wines  of  southern 
vineyards,  of  which  that  of  Madeira  may  be  taken  as  the  type. 
There  are  some  wines  which  participate  at  once  in  the  properties 
that  distinguish  the  two  varieties  thafti  have  mentioned,  or  that  show 
one  of  them  in  excess  according  to  circumstances ;  such  are  the 
wines  of  Xeres,  Alicant,  Malaga,  &c.  Some  of  these  wines  are 
what  are  called  boiled  wines,  that  is  to  say,  a  portion  of  the  must,  as 
it  flows  from  the  press,  is  concentrated  to  a  fourth  or  a  fifth  of  its 
original  bulk  by  boiling,  and  this  being  added  to  the  rest,  the  strength 
of  ilie  resulting  wine  is  increased.  Sometimes  the  concentration 
of  the  juice  is  effected  by  drying  the  grapes  partially.  It  is  in  this 
way  that  the  celebrated  Hungarian  wine,  called  Tokay,  is  prepared ; 
the  clusters  are  left  upon  the  vines  after  they  are  ripo,  and  alternate- 
ly exposed  to  the  cold  of  the  night,  which  probably  decomposes  to  a 
certain  extent  the  texture  of  the  grapes,  and  to  the  ;  eat  of  the  sun. 
They  shrivel  and  become  partially  dry.  In  this  state  the  grapes  are 
subjected  to  pressure,  and  a  very  sweet  must,  as  may  be  conceived, 


WINE. 


19t 


flows  from  hem.  In  less  favorable  climates,  where  the  rains  of  au- 
tumn prevent  the  drying  of  the  clusters  upon  the  vine  stocks,  the 
same  thing  is  effected  by  laying  the  bunches  upon  straw  in  open  or 
well-aired  granaries  or  sheds.  It  is  with  the  must  procured  from 
grapes  so  treated,  that  the  sweet  and  often  strong  wines,  which  are 
called  vins  de  paille,  or  straw  wines,  are  obtained.  Wines  when 
stored  in  the  cask  always  deposite  with  time  a  copious  sediment,  the 
lees.  This  sediment,  in  which  tartar^ predominates,  appears  to  be 
the  consequence  of  an  increase  in  the  proportion  of  alcohol  in  the 
liquor.  The  alcohol  may  increase  from  two  causes :  first,  by  the 
fermentation  which,  though  nearly  insensible,  goes  on  in  most  winea 
so  long  as  there  is  any  sugar  left  unchanged;  and  next  from  mere 
keeping.  It  is  well  known,  in  fact,  that  wine  put  into  the  best 
casks,  and  kept  in  a  well-ventilated  cellar,  loses  a  very  perceptible 
quantity  by  evaporation  ;  it  is  found  necessary  to  fill  up  the  casks 
from  time  to  time  :  the  loss  has  taken  place  through  the  pores  of 
the  wood,  in  virtue  of  an  attraction  exerted  between  the  substance 
of  the  wood  and  the  included  liquid  ;  and  as  this  attraction  is  much 
greater  between  the  organic  matter  and  water,  than  between  organic 
fibre  and  alcohol,  it  is  easy  to  conceive  how  wine  kept  in  wood 
should  improve.  The  very  same  thing,  in  fact,  appears  to  go  on  in 
regard  to  wine  in  corked  bottles  :  the  cork  does  not  oppose  all 
evaporation,  and  it  seems  probable  that  it  is  not  merely  upon  some 
new  and  little  known  change  of  a  chemical  nature  in  the  constitu- 
tion of  the  wine  that  its  improvement  and  mellowing  in  bottle  de- 
pend, but  also  upon  the  loss  of  a  certain  quantity  of  its  water  through 
the  pores  of  the  cork. 

Throwing  quality,  flavor,  &c.,  out  of  the  question,  it  is  well  known 
that  a  vineyard,  culivated  in  the  same  way,  year  after  year,  receiv- 
ing the  same  quantity  of  the  same  kind  of  manure,  of  which  the 
vintage  is  managed  in  the  same  manner,  the  wine  made  by  the  same 
method,  &c.,  yields  a  produce  which  diflfers  greatly  in  regard  to  the 
quantity  of  alcohol  it  contains  in  different  years.  The  vineyard  of 
Schmalzberg,  for  example,  near  Lampertsloch,  which  has  been 
under  my  management  for  several  years,  yields  wines  of  the  most 
dissimilar  characters  from  one  year  to  another.  Some  idea  of  this 
may  be  formed  from  the  different  quantities  of  alcohol  which  the 
wine  of  different  years  contains  : 


Tciri. 

Mean  temperature. 

Wine 
per     acre 
in  gallona. 

Pure    alco- 
hol 
per    cent. 

Pure     al- 
cohol 
per  acre, 
in  gaUons. 

Of  the  whole  term  of 
the  growtli  of  the 

Of  the  summer. 

Of  the  beginning  of 
autumn. 

1833 
1834 
1835 
1836 
1837 

deg.          deg. 

14.7C.  58.4F. 
17.3      63.1 
15.8      60.2 
15.8      60.2 
15.2      59.5 

deg.           deg. 

17.3C.  63.1F. 
20.3      68.i 
19.5      67 
21.5      71 
18,7      66 

deg.            deg. 

11.4C.  51.5F. 
17.0      63 
12.3      54 
12.2      54 
11.9      54 

311 
314 

621 
544 
184 

5.0 
11.2 
8.1 
7.1 

7.7 

11.4 
46.3 
50.0 
38.6 
14.0 

17* 


198  wiifE. 

If  we  now  inquire  how  the  meteorologica.  circumstances  of  each 
of  these  five  years  influenced  the  production  of  our  wine,  we  see  at 
once  that  the  mean  temperature  of  the  days  which  make  up  the 
period  of  the  cultivation  of  the  wine  has  a  perceptible  influence. 
The  temperature  of  the  summer  was  17.3°  C.  (63.1°  Fahr.)  of  the 
year  which  yielded  the  strongest  wine,  and  only  14.7°  C.  (58.4° 
Fahr.)  in  1833,  the  wine  of  which  was  scarcely  drinkable. 

A  hot  summer  is  naturally  /avorable  to  the  vine  :  the  mean  heat 
of  1833  did  not  exceed  17|°  C.  (63|°  Fahr.  ;)  with  the  exception  o* 
this  year,  which  must  be  regarded  as  one  of  the  very  worst,  thi> 
three  favorable  summers,  1834,  35,  and  36,  show  a  mean  tempera- 
ture of  about  20°  C.  (68°  Fahr.)  It  is  not,  however,  with  the  warm- 
est summer  that  we  find  the  strongest  wine  to  correspond.  Besides 
the  sustained  heat,  which  is  necessary  during  the  whole  year's 
growth  of  the  vine,  it  would  appear  that  a  mild  autumn  was  a  con- 
dition necessary  to  the  perfect  ripening  of  the  grapes :  this  is  one  of 
the  essential  conditions.  We  see,  in  fact,  that  in  1834,  the  months 
of  September  and  October  presented  the  extraordinary  temperature 
of  17°  C,  (62.6°  Fahr.,)  while  in  1833,  the  temperature  of  the  same 
months  did  not  rise  higher  than  11.4°  C.  (51.5°  Fahr.)  I  shall 
here  add,  that  the  year  1811,  so  remarkable  over  Europe  for  the 
quantity  and  the  excellence  of  its  wines,  was  distinguished  by  the 
high  temperature  of  the  early  part  of  its  autumn  ;  we  find,  in  fact, 
from  the  excellent  series  of  observations  with  which  M.  Herren- 
schneider  has  presented  Alsace,  that  in  this  year,  after  a  summer  the 
mean  temperature  of  which  was  19.6°  C.  (67.8°  Fahr.,)  the  heat  of 
the  months  of  September  and  October  was  maintained  at  15°  C,  (59° 
Fahr.,)  the  usual  temperature  of  the  months  of  September  and 
October  not  being  higher  than  about  11.5°  C.  (52.7°  Fahr.) 

If  we  deduct  from  these  observations  the  years  1833  and  1837, 
which  were  decidedly  bad,  it  seems  that  we  must  conclude  that  me- 
teorological influences  have  a  greater  eflfect  upon  the  quality  of 
wines,  than  upon  the  whole  quantity  of  alcohol  formed  ;  thus,  al- 
though the  wine  of  1836  was  very  inferior  to  that  of  1834,  it  actual- 
ly yielded  a  larger  proportion  of  alcohol  from  the  acre. 

In  Alsace,  in  order  that  a  year  may  be  favorable  to  the  vine,  the 
temperature  of  those  months  during  which  the  plant  is  alive  must 
be  sensibly  superior  to  the  mean  :  a  fact  which  appears  from  M. 
Herrenschneider's  long  series  of  observations.  In  a  climate  where 
the  vine  requires  such  a  condition  to  succeed,  it  is  obvious  that  its 
cultivation  can  never  be  advantageous  ;  and  this,  in  fact,  is  the  case  • 
the  cultivation  of  the  wine  would,  indeed,  be  altogether  ruinous,  were 
it  not  for  the  circumstance  that  ti  e  value  of  wine  increased  in  a 
much  greater  ratio  than  its  quality,  so  that  one  good  year  often  in- 
demnifies the  grower  for  many  bad  years.  Another  consideration 
is  this,  that  the  vine,  like  the  olive,  grows  and  thrives  in  situations 
where  it  would  be  difficuU  to  put  any  thing  else. 

The  produce  of  a  vineyard  also  depends  upon  its  age  ;  and  it 
would  be  curious  to  examine  the  progressive  increase  of  the  quanti- 
ty of  wiRe  yielded.     This  information  I  am  abJe  to  give  in  connec- 


WINE. 


190 


tion  with  a  vineyard  established  in  Flanders;  I  only  regret  that  I 
have  no  means  of  presenting  parallel  observations  from  a  countiy 
more  favorable  to  the  vine.  The  vineyard  of  Schmalzberg  was 
planted  in  1822,  with  new  cuttings  from  France,  and  from  the 
borders  of  the  Rhine.  The  vines  are  trained  as  espaliers,  and  are 
now  rather  more  than  four  feet  in  height.  The  vineyard  began  to 
yield  wine  in  1825,  and  the  following  table  shows  the  results  in  the 
successive  years  up  to  1837  : 


Years. 

Wine  per  Acre  in 
Gallons. 

Years. 

Wine  per  Acre  la 
Gallons. 

1825 

68.75 

1832 

209.9 

1826 

192.0 

1833 

311.6 

1827 

0.0 

1834 

413.4 

1828 

115.0 

1835 

620.0 

1829 

55.9 

1836 

544.5 

1830 

.  0.0 

1837 

184.4 

1831 

153.0 

The  mean  quantity  of  wine  furnished  by  this  vineyard  from  the 
date  of  its  plantation,  is  224^  gallons  per  acre.  M.  Villeneuve 
reckons  the  mean  produce  of  many  vineyards  in  the  southwest  of 
France  at  from  about  146  to  192  gallons  per  acre,  considerably  less 
consequently  than  our  vineyard  at  Schmalzberg ;  and  official  docu- 
ments, while  they  give  the  mean  produce  of  the  vine  for  the  whole 
of  France  as  170.9  gallons  per  acre,  state  the  whole  of  the  wine 
produced  over  the  country  at  976,906,414  gallons. 

From  documents  recently  published,  the  whole  produce  of  the 
vineyards  of  the  German  States  brought  to  market  appears  to  be 
59,180,000  gallons. 

Pulque.  This  is  a  vinous  liquor,  indigenous  to  Mexico  and  some 
parts  of  Peru,  and  is  prepared  from  the  sap  of  the  Agave  Americana. 
When  this  plant  is  about  to  flower,  a  hole  is  made  into  the  upper 
part  of  its  stem,  which  by  and  by  becomes  filled  with  juice,  and  is 
removed  two  or  three  times  in  the  course  of  the  twenty-four  hours ; 
this  sap  is  very  sweet,  runs  quickly  into  fermentation,  and  yields  the 
liquor  called  pulque.  The  flow  of  sap  continues  for  two  or  three 
moB  :hs,  and  a  single  plant  will  yield  from  six  to  eight  quarts  per 
day.  In  the  neighborhood  of  a  large  town,  which  ensures  a  ready 
sale  for  the  produce,  a  plantation  of  Agave  is  one  of  the  most  pro- 
fitable possessions  ;  in  the  neighborhood  of  Cholula  there  are  singia 
plantations  which  are  worth  from  jG8,000  to  jCl2,000. 


200  SOIL. 


CHAPTER  ;V. 


OF  SOILS. 


The  solid  mass  of  our  earth  does  not  everywhere  present  the 
same  physical  characters,  or  the  same  chemical  composition.  In 
traversing  a  mountainous  country  of  any  extent,  we  seldom  fail  to 
observe  a  notable  difference  in  the  nature  and  relative  position  of  the 
rocks  which  compose  it ;  the  idea  which  forces  itself  upon  the  mind 
in  such  circumstances  is,  that  these  mineral  masses  have  not  had 
the  same  origin,  that  they  have  been  formed  and  placed  in  their 
several  situations  at  distinct  and  often  distant  epochs. 

In  examining  attentively  the  inequalities  whicn  mark  the  surface 
of  the  globe,  we  soon  perceive  that  those  rocks  which  generally 
form  the  most  elevated  points,  the  axis  or  skeleton  of  mountain 
chains,  result  from  the  agglomeration  or  intimate  mixture  of  different 
mineral  substances  which  may  be  isolated  and  separately  studied. 

These  crystalline  masses  are  frequently  covered  to  a  certain 
depth,  and  even  completely  concealed  by  rocks  of  more  recent  for- 
mation, the  fragmentary  elements  of  which  proclaim  their  origin 
from  the  attrition  or  breaking  down  of  the  strata  which  support 
them.  The  regular  stratification  of  these  superimposed  rocks,  the 
configuration  of  their  minute  particles,  the  remains  of  organized  beings 
which  are  found  in  them,  proclaim  them  to  be  deposites  which  have 
taken  place  successively,  and  from  the  ocean.  The  formation  of  the 
crystalline  rocks  probably  dates  from  the  period  at  which  the  crust 
of  the  globe  became  solid.  These  elements,  intimately  mingled  by 
fusion,  combined  as  they  cooled,  according  to  the  laws  of  affinity,  to 
constitute  the  mineral  species  which  we  encounter ;  just  as  it  hap- 
pens that  mineral  species,  identical  with  those  which  we  observe  in 
nature,  are  produced  and  crystallize  during  the  consolidation  of  cer- 
tain scoriae  from  our  furnaces. 

The  various  circumstances  which  have  accompanied  the  cooling 
o''  the  crust  of  the  globe,  have  doubtless  occasioned  the  differences 
wnich  we  observe  in  the  distribution  of  the  minerals  that  enter  into 
the  composition  of  rocks.  Thus  granite  and  mica  schist,  which  pre- 
sent so  dissimilar  a  structure,  are  nevertheless,  and  very  certainly, 
varieties  of  the  same  species,  and  contain  quartz,  felspar,  and  mica. 
In  sienite,the  mica  is  replaced  by  amphibolite,  and  in  protogenite  by 
talc.  In  trachite,  a  volcanic  rock,  both  of  older  and  more  recent 
date,  quartz  is  almost  entirely  wanting  ;  the  amphibolite  is  replaced 
by  pyroxenite,  and  the  felspar  which  is  encountered,  is  no  longer 
identical  in  its  chemical  composition  with  that  which  enters  into  the 
constitution  of  granite.  The  limestone  rock,  which  belongs  to  the 
same  Plutonic  epoch,  is  granular  or  saccharoid  ;  occasionally  the 
intervention  of  magnesia  makes  it  pass  into  iolomite. 

The  sedimentary  strata  do  not  vary  less  io  their  composition.    Ths 


OIL.  201 

causes  which  segregated  the  rocks  of  igneous  origin,  appear  to  have 
destroyed  or  removed  one  or  several  of  their  elements  before  their 
new  consolidation  ;  one  of  the  most  common  deposites,  sandstone  or 
grit,  is  almost  wholly  composed  of  grains  of  quartz,  amidst  which 
particles  of  mica  are  frequently  encountered  ;  but  felspar  is  ex- 
tremely rare.  In  the  oldest  sedimentary  strata  of  the  series,  as  in 
the  greywackes,  the  igneous  elements  are  met  with  more  complete, 
and  less  altered.  The  structure  of  the  calcareous  rocks  of  this 
epoch  is  often  compact,  clayey  ;  it  becomes  porous  and  friable  in 
deposites  of  more  recent  date. 

The  stratified  rocks  must  have  been  deposited  in  parallel  superim- 
posed layers,  and  these  strata,  horizontal  in  the  beginning,  have  been 
forced  into  the  inclined  and  perpendicular  positions  which  they  now 
occupy  by  the  tumefaction  or  rising  of  the  masses  upon  which  they 
rest.  The  organic  remains  which  they  present,  frequently  in  such 
quantity,  proclaim  that  in  the  period  when  the  revolutions  of  the 
globe  took  place  that  gave  them  birth,  there  were  already  animated 
beings  and  plants  growing  upon  the  surface  of  the  earth.  The  pro- 
duction of  sedimentary  strata,  is  an  obvious  proof  that  the  igneous 
rocks  of  which  they  are  the  product,  must  have  been  segregated,  so 
as  to  form  beds  of  gravel,  and  sand,  and  clay.  The  elements  of  all 
stratified  rocks  must  necessarily  have  passed  through  these  different 
stages  before  the  powerful  causes  which  consolidated  them,  of  the 
nature  of  which  we  cannot  now  form  an  estimate,  came  into  play. 
The  disintegration  of  the  crystalline  igneous  rocks  proceeds  under 
our  eyes,  as  it  were,  from  the  combined  actions  of  water  and  the  at- 
mosphere. 

Water,  by  reason  of  its  fluidity,  penetrates  the  masses  of  rocks 
that  are  at  all  porous ;  it  filters  into  their  fissures.  If  the  tempera- 
ture now  fall,  and  the  water  comes  to  congeal,  it  separates  by  its 
dilatation  the  molecules  of  the  mineral  from  one  another,  destroys 
their  cohesion,  and  produces  clefts  which  slowly  reduce  the  hardest 
rocks  to  fragments,  and  then  to  powder.  During  the  frozen  state^ 
the  ice  may  serve  as  a  cement,  and  connect  the  disintegrated  parti- 
cles ;  but  with  the  thaw,  the  slightest  force,  currents  of  water,  the 
mere  effect  of  weight,  suffices  to  carry  the  fragments  to  the  bottom 
of  the  valley,  and  the  rubbing  and  motion  to  which  these  fragments 
of  rocks  are  exposed  in  torrents,  tend  to  break  them  still  smaller,  and 
to  reduce  them  to  sand. 

The  quantity  of  earthy  matter  brought  down  by  streams  and  rivers, 
is  coripiderable  :  an  idea  may  be  formed  of  it  from  the  thickness  of 
the  slime  or  mud  deposited  by  a  river  which  has  overflowed  its  banks 
In  many  situations,  the  arable  soil  is  either  formed  entirely,  or  is 
powerfully  ameliorated  by  such  alluvial  deposites.  The  fertilizing 
powers  of  the  mud  of  the  Nile  are  well  known  ;  according  to  Shaw, 
the  waters  of  this  river  carry  with  them  about  the  132d  part  of  their  vol- 
ume ;  those  of  the  Rhine,  at  the  periods  of  its  great  increase,  bring  down 
more  than  the  100th  part ;  and  Dr.  Barrow,  from  observations  made 
in  China,  estimates  at  the  200th  part  of  the  volume  of  the  mass  of 
iiuidi  the  mud  and  slime  which  are  cariied  towards  the  sea  by  tho 


202  SOIL. 

Yellow  river.  These  fluviatile  deposites  accumulate  £t  vhe  mouths 
of  great  rivers,  and  gradually  encroach  upon  the  ocean  ;  ihis  is  very 
conspicuous,  for  example,  at  the  mouths  of  the  Elbe,  where,  at  the 
turn  of  the  tide,'  when  there  is  an  interval  of  calm,  the  earthy  mat- 
ters which  are  held  in  suspension  are  precipitated,  and  a  sediment 
results,  which  is  thrown  up  by  the  next  waves  upon  the  beach.  By 
these  successive  deposites,  the  beach  rises  gradually,  and  an  extensive 
alluvium  is  formed  which  remains  dry  at  neap  and  ordinary  tides. 
These  new  lands,  the  fertility  of  which  is  truly  surprising,  constitute 
the  polders  of  whicl  ihe  Dutch  make  so  much.  During  spring 
tides,  and  storms  from  particular  quarters,  these  polders  would  of 
course  be  all  submerged,  had  not  the  active  industry  of  the  inhabit- 
ants raised  dykes,  which  successfully  oppose  the  waters  of  the 
ocean. 

Besides  the  mechanical  causes  of  the  destruction  of  rocks  al- 
ready quoted,  there  is  a  chemical  action  depending  upon  meteoro- 
logical influences,  which  exerts  a  powerful  influence  upon  the  con- 
stituent elements  of  crystalline  rocks.  Felspar,  amphibolite,  mica, 
and  the  protoxide  of  iron  suffer  decomposition  in  certain  circum- 
stances with  surprising  rapidity,  without  our  being  able  to  foresee, 
and  still  less  to  explain,  this  singular  tendency  to  destruction.  In 
granite,  for  example,  the  felspar  and  the  mica  lose  their  vitreous 
and  crystalline  state,  they  become  friable,  earthy,  and  are  trans- 
formed into  an  argillaceous  substance,  which  is  known  in  the  arts 
under  the  name  of  kaoline,  and  which  is  extensively  used  m  the 
manufacture  of  porcelain  ;  amphibolite,  and  pyroxenite,  undergo  an 
alteration  of  the  same  kind.  In  these  minerals  the  protoxide  of  iron 
passes  to  the  state  of  the  maximum  of  oxidation.  The  air  and 
moisture  appear  to  exert  a  great  influence  upon  this  alteration,  which 
frequently  extends  to  a  great  depth,  as  we  see  in  the  beds  of  porce- 
lain earth,  which  are  worked  in  various  granite  districts,  and  as  I 
have  myself  ascertained,  in  a  bed  of  decomposed  syenitic  porphyry 
where  there  are  very  extensive  subterraneous  works.  In  these 
works,  which  are  carried  on  in  auriferous  strata,  the  alteration  in 
the  felspar  and  amphibolite  can  be  followed  to  a  depth  of  nearly  330 
feet.  In  the  midst  of  the  rocks  so  changed,  we  every  here  and  there 
meet  with  masses  which  have  resisted  the  decomposing  action,  and 
still  possess  all  their  original  hardness  and  freshness.  Historical 
monuments  also  show  us  unalterable  granites  ;  such  is  that,  for  in- 
stance, which  now  forms  the  obelisk  ir/  the  square  of  San  Giovanni 
di  I^aterano  at  Rome,  and  which  was  cut  at  Siena,  under  the  reign 
of  a  king  of  Thebes,  thirteen  hundred  years  before  the  Christian  era. 
Such  is  further  the  obelisk  of  the  Place  of  St.  Peter,  which  was 
consecrated  to  the  sun  by  a  son  of  Sesostris  more  than  three  thou- 
sand years  ago. 

The  schists,  by  reason  of  their  structure,  wear  away  with  much 
greater  facility.  Calcareous  rocks  resist  atmcvpherical  agencies 
somewhat  better  ;  but  their  softness  in  general  suffers  them  to  be 
readily  attacked  by  mechanical  causes,  and  water  even  acts  upon 
hem  as  a  sdveat  through  the  medium  of  the  carbonic  acid  which 


SOIL.  203 

it  always  contains.  The  resistance  of  the  gre}Wackes,  and  of  the 
sandstones  depends  in  a  great  measure  ou  the  nature  and  cohesion 
of  the  cement  which  unites  their  particles;  their  power  of  resisting, 
however,  is  generally  inconsiderable,  and  these  rocks  fall  down 
pretty  rapidly  into  sandy  soils. 

The  modifications  experienced  hy  the  constituent  minerals  of 
rocky  masses,  do  not  happen  solely  from  changes  in  the  molecular 
state  of  their  elements ;  their  chemical  nature  is  further  deeply 
changed,  and  some  of  their  original  principles  disappear.  The  fel- 
spars, for  example,  into  the  constitution  of  which  potash  and  soda 
enter,  abandon  almost  the  whole  of  these  alkalies,  in  passing  into 
the  state  of  kaoline.  This  is  made  manifest  by  a  comparison  of  the 
analyses  of  the  mineral  in  its  two  states.  Besides  the  alkali  which 
is  lost,  we  also  perceive  that  in  kaoline,  the  proportion  of  alumen 
relatively  to  that  of  silica,  is  much  greater  than  in  the  undecomposed 
felspar,  a  fact  which,  according  to  M.  Berthier,  demonstrates  that 
the  alkali  is  removed  in  the  state  of  silicate. 

The  final  result  of  the  disintegration  of  rocks,  and  of  the  decom- 
position of  the  minerals  which  enter  into  their  constitution,  is  the 
formation  of  those  alluviums  which  occupy  the  slopes  of  mountains 
that  are  not  too  steep,  the  bottoms  of  valleys,  and  the  most  extensive 
plains.  These  deposites,  however  formed,  whether  of  stones,  peb- 
bles, gravel,  sand,  or  clay,  may  become  the  basis  of  a  vegetable  soil, 
if  they  are  only  sufficiently  loose  and  moist.  Vegetation  of  any  kind 
succeeds  upon  them  at  first  with  difficulty.  Plants  which  by  their 
nature  live  in  a  great  measure  at  the  expense  of  the  atmosphere,  and 
whick  ask  from  the  earth  little  or  nothing  more  than  a  support,  fix 
themselves  there  when  the  climate  permits.  Cactuses  and  fleshy 
plants  take  root  in  sands ;  mimosas,  the  broom,  the  furze,  &c.,  show 
themselves  upon  gravels.  These  plants  grow,  and  after  their  death, 
either  in  part  or  wholly,  leave  a  debris  which  becomes  profitable  to 
succeeding  generations  of  vegetables.  Organic  matter  accumulates 
in  the  course  of  ages,  even  in  the  most  ungrateful  soils  in  this  way, 
and  by  these  repeated  additions  they  become  less  and  less  sterile. 
It  is  probable  that  the  virgin  forests  of  the  new  world  have  thus 
supplied  the  wonderful  quantity  of  vegetable  mould,  in  which  the 
present  generation  of  trees  is  rooted.  At  Lavega  de  Supia,  in  South 
America,  the  slipping  of  a  porphyritic  mountain  covered  completely 
with  its  debris,  to  the  extent  of  nearly  half  a  league,  the  rich  plan- 
tations of  sugar-cane  which  were  there  established.  Ten  years  af- 
terwards I  saw  the  blocks  of  porphyry  shadowed  by  thick  groves  of 
mimosas ;  and  the  time  perchance  is  not  very  remote  when  this  new 
forest  will  be  cleared  away,  and  the  stony  soil,  enriched  with  its 
spoils,  will  be  restored  to  the  husbandman. 

The  chemical  composition  of  the  earth,  adapted  for  vegetation, 
must  of  course  participate  in  the  nature  of  the  rocks  and  substrata 
from  which  it  is  derived ;  and  the  elements  which  enter  into  the 
constitution  of  mineral  species  ought  to  be  found  in  the  soils,  which, 
•y  the  effect  of  time  or  human  industry,  may  serve  for  the  repro- 
duction of  regetables.     It  is  on  this  account  that  it  becomes  inter* 


204 


SOIL. 


esting  to  know  the  composition  of  the  minerals  which  are  the  most 
abundantly  dispersed  in  the  solid  mass  of  the  globe. 

The  solid  part  of  our  planet,  as  is  well  known,  occupies  but  one 
third  of  its  whole  surface.  The  ocean  occupies  two-thirds,  and  the 
majority  of  the  rocks  of  sedimentary  formation  must  have  been  pri- 
marily deposited  at  the  bottom  of  the  sea.  These  rocks  will  there- 
fore be  apt  to  contain  the  saline  substances  which  are  met  with  in 
sea-water,  and  it  is  a  fact  that  many  of  the  secondary  sandstones 
show  unequivocal  traces  of  these  substances.  Deltas  and  low  downs, 
left  by  the  ocean,  are  constantly  being  brought  under  tillage,  and  the 
fierce  winds  of  the  sea  frequently  carry  saline  matters  to  vast  dis- 
tances, even  to  the  centre  of  great  continents;  lastly,  .as  we  shall 
see  by  and  by,  the  ocean  supplies  agriculture  with  powerful  manures. 
Analysis  shows  that  sea-water  contains,  besides  chloride  of  sodium 
or  common  salt,  hydrochlorate  of  magnesia,  sulphate  of  snd^  sul- 
phate of  magnesia,  sulphate  of  lime,  carbonate  of  lime,  caroonate  of 
magnesia,  and  a  quantity  of  carbonic  acid,  to  which  must  be  added 
the  substances  discovered  in  the  mother  waters  of  salt  marshes,  and 
which  occur  with  reference  to  the  others  in  quantities  so  small  as  to 
escape  direct  analyses  of  any  moderate  portions  of  sea-water  :  these 
substances  are  iodides,  bromides,  and  certain  ammoniacal  salts. 

The  minerals  most  generally  found  in  rocks  are  quartz,  felspar, 
mica,  amphibolite,  pyroxenite,  talc,  serpentine,  and  diallage. 

Quartz  is  frequently  composed  of  silica  nearly  in  a  state  of  purity  ; 
but  I  may  save  time  by  presenting  in  a  single  table  the  composition 
of  the  principal  mineral  species  such  as  we  find  it  indicated  by  the 
best  chemical  analysts  : 


Minerals. 

COMPOSITION. 

1 
1 

Alu- 
mina. 

Lime. 

Mag- 
nesia. 

1 

1 

1 

5^ 

III 
5^' 

•U 

i^ 

■^ 

i 

Felspar  of  Lomnitz  .... 

Ditto  Domite 

Ditto  Albite  of  Finland 
Ditto  Albite  of  Arendul 

66.8 
61.0 
08.0 
68.7 
42  0 
48.5 
45.7 
54.6 
54.9 
42.3 
43.1 
47.2 
58.2 
62.0 

17.5 
19.2 
19.6 
199 
16.1 
33.9 
12.2 

0.2 

0.3 

3.7 

traces 

1.3 
0.7 

13.8 
24.9 
23.6 

0.5 
13.1 

1.6 

traces 
26.0 

18.8 
18.0 
16.5 
44.2 
40.4 
24.4 
33.2 
30.5 

12.0 
11.5 

7.6 
11.3 

2.8 

11.1 
9.1 

0.8 
4.2 
0.2 
0.3 
4.9 

7.3 

1.8 
4.4 
0.2 
1.2 
7.4 
4.6 
2.5 

0.5 
traces 

1.3 
0.2 
2.0 
0.4 

0.7 
1.5 

2.0 

3.0 

1.3.3 
12.5 
3.2 
3.5 
0.5 

Mica  from  the  U.  States 
Amphibolite  of  Pargas  . 
White  Pyroxenite 

Ditto,  another  kind  .... 

Spezian  Diallage  

Talc  from  St.  Bernard. . 
Ditto  from  St  Gothard. . 

If  we  now  compare  the  analyses  of  the  ashes  of  vegetables  which 
we  have  already  given  with  those  just  indicated,  we  see  that  the 
mineral  substances  which  meet  us  in  plants  ilsc  exist  in  the  soil  in 
dependenlly  of  any  addition  from  manure.     We   nay  therefore  lay  jl 


SOIL.  205 

down  as  a  principle  that  the  mineral  substances  encountered  in  vege- 
tables are  obtained  in  the-  soil,  and  that  tlie  whole  of  these  substan'ces 
come  from  rocks  which  form  the  solid  crust  of  our  planet.  I  ought, 
however,  to  observe  in  this  place  that  the  phosphates,  which  are  so 
constantly  present  in  plants  that  it  is  to  be  presumed  they  are  essen- 
tial to  their  orijanization,  do  not  figure  among  the  elements  of  crys- 
talline rocks ;  we  only  meet  with  phosphoric  acid  in  the  strata  of  a 
more  recent  geological  epoch, — strata  the  formation  of  which  has  in- 
deed followed  the  appearance  of  organized  beings  ;  so  that  it  would 
be  quite  fair  to  mamtam  that  this  acid  had  been  introduced  intc 
those  new  strata  by  the  animated  beings  which  are  buried  in  them. 
Still  the  phosphatfes  are  by  no  means  wanting  in  the  rocks  of  igne- 
ous origin.  In  metalliferous  strata,  to  quote  those  of  more  common 
occurrence  only,  we  find  phosphate  of  lead,  of  copper,  of  manganese, 
and  of  lime  ;  it  is  even  difficult  to  discover  a  ferruginous  mineral 
which  does  not  contain  a  larger  or  smaller  dose  of  phosphoric  acid. 
And  I  must  here  add,  that  if  phosphoric  acid  has  been  rarely  indi- 
cated as  a  constituent  of  mineral  substances,  this  is  by  no  means 
from  its  uniform  absence  there,  but  because  it  escaped  the  researches 
of  the  analyst,  in  the  same  way  as  iodine  and  bromine  for  a  long  time 
escaped  notice  in  all  the  analyses  that  were  made  of  sea-water. 
Chemists,  in  fact,  only  discover  those  bodies  readily  which  exist  in 
some  very  appreciable  quantity  in  the  compounds  they  examine. 
The  substances  whose  presence  is  not  foreseen,  those  which  only 
enter  in  extremely  small  quantity  into  a  mineral,  are  apt  to  pass  the 
eyes  of  even  the  most  skilful  and  conscientious  unperceived. 

The  ashes  of  every  vegetable  examined  up  to  the  present  time 
show  us  phosphates,  and  yet  these  salts  have  never  been  detected 
in  any  of  the  analyses  of  saps  (not  very  numerous  it  is  true)  which 
we  possess ;  it  is,  nevertheless,  all  but  certain  that  the  sap  must 
contain  phosphoric  acid  in  some  state  of  combination  or  another. 

Thaer  compares  the  soil  in  husbandry  to  the  raw  material  upon 
which  the  industry  of  the  manufacturer  is  exercised  ;  the  comparison 
would,  perhaps,  be  more  exact  were  the  soil  likened  to  the  mechani- 
cal agents  he  uses ;  and,  in  fact,  even  as  the  prosperity  of  manufac- 
tures and  the  perfection  of  their  produce  depend  upon  the  perfection 
of  the  machinery  employed,  so  are  the  quality  and  the  quantity  of 
crops  connected  in  the  most  intimate  manner  with  the  quality  of  the 
soil.  The  highest  skill  of  the  husbandman,  even  under  a  favorable 
climate,  and  otherwise  in  the  most  advantageous  circumstances,  may 
all  be  made  nugatory  by  the  incessantly  renewed  difficulties  which 
meet  him  in  a  barren  soil. 

To  be  truly  fit  for  agriculture  the  earth  ought  to  present  several 
essential  qualities  ;  a  soil,  for  instance,  must  be  sufficiently  open, 
sufficiently  loose,  to  permit  the  roots  of  plants  to  penetrate  it,  and  to 
prevent  the  water  from  stagnating  upon  it.  The  matter  of  which  it 
is  composed  must,  further,  be  of  such  a  kind  that  the  air  may  insinu- 
ate itself  into  it  and  be  renewed,  without,  however,  too  rapid  a  des- 
iccation following. 

A  great  deal  has  been  written  since  Bergman's  time  upon  th« 

18 


206  SOIL SAND  AND   CLAY. 

chemical  composition  of  soils  Chemists  of  great  talent  have  made 
mafny  complete  analyses  of  soil  ;  noted  for  their  fertility  ;  still  practical 
agriculture  has  hitherto  deriv^id  very  slender  benefits  from  labors  of 
this  kind.  The  reason  of  this  is  very  simple  ;  the  qualities  which  we 
esteem  in  a  workable  soil  depend  almost  exclusively  upon  the  me- 
chanical mixture  of  its  elements  ;  we  are  much  less  interested  in  its 
chemical  composition  than  in  this;  so  that  simple  washing,  which 
shows  the  relations  between  the  sand  and  the  clay,  tells,  of  itself,  much 
more  that  is  important  to  us  than  an  elaborate  chemical  analysis. 
The  quality  of  an  arable  soil  depends  essentially  on  the  association 
of  these  two  matters.  Sand,  whether  it  be  silicious,  calcareous,  or 
felspathic,  always  renders  a  soil  friable,  permeable,  loose  ;  it  facili- 
tates the  access  of  the  air  and  the  drainage  of  the  water,  and  its  in- 
fluence is  more  or  less  favorable  as  it  exists  in  the  state  of  minute 
subdivision,  or  in  the  state  of  coarse  sand  or  of  gravel. 

Clay  possesses  physical  properties  entirely  opposed  to  those  of 
sand ;  united  with  water  it  forms  an  adhesive  plastic  paste,  which, 
once  moistened,  becomes  almost  impermeable.  With  such  charac- 
ters, it  will  easily  be  conceived  how  it  is  impossible  to  work  to  ad- 
vantage a  soil  that  is  entirely  argillaceous.  The  proper  character, 
or,  if  you  will,  the  quality  of  a  soil,  depends,  then,  essentially  on 
the  element  which  predominates  in  the  mixture  of  sand  and  clay  that 
composes  it ;  and  between  the  two  extremes,  which  are  alike  un- 
favorable to  vegetation,  viz.,  the  completely  sandy  soil  and  the  un- 
mixed clay,  all  the  other  varieties,  all  the  intermediate  shades  can 
be  placed.  It  is  rare,  indeed,  that  arable  soils  are  formed  solely  of 
sand  and  clay  :  not  to  mention  certain  saline  substances  which  are 
generally  encountered,  although  in  small  quantity,  we  always  find 
the  remains  of  organic  matters,  remains  which  constitute  that  part 
of  a  soil  which  has  been  designated  under  the  somewhat  vague  name 
of  humus.  Although  a  soil  which  is  entirely  without  humus  may  be 
cultivated  by  calling  in  the  aid  of  manure,  and  as  humus,  consequent- 
ly, need  not  be  regarded  as  indispensable,  still  this  matter  generally 
enters,  in  certain  proportions,  into  the  constitution  of  soils.  The 
soils  of  forest  lands  contain  a  large  quantity  of  it,  and  some  soils  are 
mentioned  which  are  very  rich  in  this  substance,  and  which  yield 
abundant  irops  of  grain  for  ages,  and  with  very  little  attention. 

In  examining  a  soil,  attention  ought  to  be  directed,  1st,  to  the 
sand,  2d,  to  the  clay,  3d,  to  the  humus  which  it  contains.  It  would, 
further,  be  useful  to  inquire  particularly  in  regard  to  certain  other 
principles  which  exert  an  unquestionable  influence  upon  vegetation, 
such  as  certain  alkaline  and  earthy  salts. 

Vegetable  earth  dried  in  the  air  until  it  becomes  quite  friable 
may,  nevertheless,  still  retain  a  considerable  quantity  of  water,  and 
which  can  only  be  dissipated  by  the  assistance  of  a  somewhat  high 
temperature.  It  is  therefore  proper,  in  the  first  instance,  to  bring 
all  the  soils  which  it  is  proposed  to  examine  comparatively,  to  one 
constant  degree  of  dryness.  The  best  and  quickest  way  ff  drying 
such  a  substance  as  a  portion  of  soil,  is  to  make  use  of  the  oil-bath ; 
a  qiantity  of  oil  contained  in  a  copper  vessel  is  readily  kept  at  ai 


SOIL ITS  ANALYSIS.  207 

almost  uniform  temperature  by  means  of  a  lamp.  A  thermometer 
plunged  in  the  bath  shows  the  degree  to  which  it  is  heated  ;  the 
substance  to  be  dried  is  put  into  a  glass  tube  of  no  great  depth,  and 
sufficiently  wide  ;  or  into  a  porcelain  or  silver  capsule,  if  the  quantity 
to  be  operated  upon  be  somewhat  considerable  :  these  tubes,  or  ves- 
sels, are  placed  in  the  oil  so  as  to  be  immersed  in  it  to  about  two- 
thirds  of  their  height.  For  the  desiccation  of  soils,  the  temperature 
may  be  carried  to  150"  or  160°  C,  (334°  or  352°  F.)  The  weight 
of  the  vessel  is  first  accurately  taken,  and  a  given  weight  of  the 
matter  to  be  dried  is  then  thrown  into  it,  after  which  it  is  exposed  to 
the  action  of  the  bath.  If  we  operate  upon  from  600  to  700  grains, 
the  drying  must  be  continued  during  two  or  three  hours;  the  weight 
of  the  capsule  with  its  contents,  after  having  been  wiped  thoroughly 
clean,  is  then  taken.  It  is  placed  anew  in  the  bath,  and  its  weight  is 
taken  a  second  time  after  an  interval  of  fifteen  or  twenty  minutes ; 
if  the  weight  has  not  diminished,  it  is  a  proof  that  the  drying  was 
complete  at  the  time  of  the  first  trial.  In  the  contrary  case,  the 
operation  must  be  continued,  and  no  drying  must  be  held  terminated, 
until  two  consecutive  weighings*  made  at  an  interval  of  from  fifteen 
to  twenty  minutes,  show  any  thing  more  than  a  very  trifling  differ- 
ence. Davy  points  out  another  and  much  more  simple  method, 
which,  although  far  from  accurate,  may,  nevertheless,  suffice  Id 
many  general  trials.  The  soil  to  be  dried  is  put  into  a  porcelain 
capsule  heated  by  a  lamp,  and  a  thermometer,  with  which  the  mass 
may  be  stirred,  is  placed  in  its  middle,  and  shows  the  temperature  at 
each  moment.  Lastly,  in  many  circumstances  the  marine  bath  may 
suffice.  In  drying,  the  main  point  is  to  do  so  at  a  known  tem- 
perature, and  one  which  may  be  reproduced;  for  the  absolute  desic 
cation  of  a  quantity  of  soil  could  not  be  accomplished  except  at 
a  heat  close  upon  redness,  and  this  would,  of  course,  alter  or  destroy 
the  organic  matters  it  contains. 

The  organic  matters  contained  in  ordinary  soils  consist,  in  part, 
of  pieces  of  straw  and  of  roots,  which  are  usually  separated  by 
sifting  the  earth  through  a  hair  sieve  ;  the  gravel  and  stones  which 
the  soil  contains  are  separated  in  the  same  way. 

The  earth  sifted  is  now  washed.  To  accomplish  this,  it  is  intro 
duced  into  a  matrass,  w  hh  three  or  four  times  its  bulk  of  hot  distilled 
water,  the  whole  is  shaken  well  for  a. time,  the  matrass  is  left  to 
stand  for  a  moment,  and  then  the  liquid  is  decanted  into  a  wide 
porcelain  capsule.  The  washing  is  continued,  fresh  quantities  of 
water  being  added  each  time,  until  the  whole  of  the  clay  has  been  re- 
moved, which  is  known  by  the  fluid  becoming  clear  very  speedily  ; 
the  sand  which  remains,  is  then  washed  out  into  another  capsule. 
The  argillaceous  particles,  or  the  clay  and  all  the  matters  held 
in  suspension  in  the  water,  are  thrown  upon  a  filter  and  dried ; 
the  desiccation  is  completed  by  the  same  process,  and  under  the 
same  circumstances  as  that  of  the  soil  had  been.  The  sand  is, 
in  like  manner,  dried  with  the  same  care. 

If  we  would  ascertain  the  nature  and  quantity  of  the  soluble  salts^ 
the  whole  of  the  water  used  in  the  washing  must  be  put  togcthei 


208  SOIL ITS   ANALYSIS. 

and  evaporated,  which  may  be  dona  upon  a  sand-bath.  The  evapo* 
ration  is  pushed  to  dryness,  and  thi  salts  that  remain,  having  been 
previously  weighed,  are  thrown  into  a  small  platinum  capsule,  in 
which  they  are  heated  to  a  dull  red  by  means  of  a  spirit-lamp,  in 
order  to  burn  out  the  organic  salts,  and  thus  distinguish,  by  means 
of  a  subsequent  weighing,  between  them  and  the  inorganic  salts. 

The  sand  may  be  silicious  or  calcareous.  The  presence  of  car- 
bonate of  lime  is  readily  ascertained  by  treating  it  with  an  acid  which 
will  form  a  soluble  salt  with  lime,  such  as  hydrochloric,  nitric,  or 
acetic  acid.  Effervescence  shows  the  presence  of  a  carbonate  ;  the 
quantity  of  which  may  be  estimated  by  weighing  the  sand  dry  before 
and  after  its  treatment  with  the  acid,  particular  care  being  of  course 
taken  to  wash  the  remaining  sand  well  before  setting  it  to  dry. 
This,  however,  is  an  operation  of  little  use,  the  great  object  is  to  as- 
certain the  quantity  of  sandy  matter.  Had  we  a  particular  interest 
in  ascertaining  the  presence  and  estimating  the  quantity  of  the  earthy 
carbonates  contained  in  a  sample  of  soil,  it  would  be  advisable  to 
make  a  special  inquiry,  inasmuch  as  the  finely  divided  calcareous 
earth  being  carried  off  along  with  the  clay  in  the  course  of  the  wash- 
ing, the  sand  obtained  never  contains  the  whole  of  the  carbonate  of 
lime. 

The  argillaceous  matter  procured  by  the  washing  is  far  from  being 
pure  clay :  it  contains  a  quantity  of  extremely  fine  sand,  particles 
of  calcareous  earth,  and  if  the  soil  contain  humus,  the  more  delicate 
particles  of  this  substance  will  also  be  included. 

To  determine  the  quantity  of  humus,  recourse  is  generally  had  to 
its  destruction  by  heat.  A  known  weight  of  dried  earth  is  heated 
to  redness  in  a  capsule,  and  constantly  stirred  for  a  time,  and  when 
no  more  of  those  brilliant  points  or  sparks,  which  are  indications  of 
the  combustion  of  carbon,  are  observed,  it  is  set  to  cool  and  then 
weighed.  This  is  the  method  which  has  been  generally  followed  by 
Davy  and  others.  It  would  be  difficult  to  find  a  method  more  con- 
venient than  this,  but  it  is  unfortunntely  very  inaccurate.  Soils 
dried  at  a  temperature  at  which  organic  matter,  such  as  humus,  &c., 
begins  to  change,  still  retain  a  considerable  quantity  of  water  in  union 
with  the  clay.  This  water  is  disengaged  at  the  red  heat  required 
for  the  combustion  of  the  organic  matters  ;  and  as  their  quantity  is 
estimated  by  the  loss  of  weight  on  the  subsequent  weighing,  it  is  ob- 
vious that  the  loss  from  the  dissipation  of  water  is  added  to  that 
which  proceeds  from  the  destruction  of  the  humus.  It  is  undoubted- 
ly to  this  cause  of  error  that  we  must  ascribe  the  large  proportions 
of  humus  mentioned  in  the  soils  examined  by  Thaer  and  Einhoff ;  it 
is  therefore  better  to  restrict  the  examination  to  the  determination 
of  the  presence  or  absence  of  humus  than  to  attempt  to  ascertain  its 
quantity  by  so  imperfect  a  method. 

Priestley  and  Arthur  Young  were  already  aware  that  a  more  deli- 
cate operation  was  required  to  determine  the  quantity  of  humus. 
They  recommend  calcination  of  the  soil  in  a  close  vessel,  and  that 
the  gaseous  products  should  be  collected.  This  mode  of  proceeding, 
however,  would  have  but  slight  advantages  over  that  which  I  hava 


SOIL ITS    ANALYSIS.  209 

just  criticised,  inasmuch  as  the  volume  of  gas  collected  varies  with 
every  difference  of  heat  employed. 

The  only  method  in  my  opinion  which  we  have  of  learning  the 
quantity  of  humus,  of  organic  debris,  which  is  contained  in  a  soil, 
is  that  of  an  elementary  analysis.  It  is  by  burning  a  known  quanti- 
ty of  earth  thoroughly  dried  by  means  of  the  oxide  of  copper,  aided 
by  a  current  of  oxygen,  that  the  carbon  and  hydrogen  may  be  de- 
termined. But  the  most  important  point  of  all  is  to  ascertain  the 
amount  of  azote  included  in  the  organic  remains  of  the  soil ;  and  we 
have  happily  precise  means  in  our  elementary  analysis  of  ascertain- 
ing the  quantity  of  azote,  from  which  the  amount  of  azotized  organic 
matter  may  be  accurately  inferred. 

It  may  be  very  useful  to  determine  the  presence  or  absence  of 
carbonate  of  lime  in  a  so  1 ;  this  knowledge  would  of  course  guide 
us  in  our  applications  of  lime,  marl,  &c.  Two  modes  may  be  em- 
ployed for  this  purpose ;  1st.  the  soil  may  be  treated  by  nitric  acid 
slightly  diluted  with  water.  Any  effervescence  will  denote  the 
presence,  in  all  probability,  of  carbonate  of  lime.  I  say  in  all  proba- 
bility, because  the  disengagement  of  carbonic  acid  gas  under  such 
circumstances  generally  indicates  the  presence  of  carbonate  of  lime  ; 
it  is  not,  however,  a  special  character,  because  the  disengagement 
may  be  due  to  the  presence  of  any  other  carbonate.  It  is  well  to 
boil  the  acid  solution  upon  the  sample  of  soil  that  is  analyzed  ;  the 
part  which  is  not  dissolved  is  thrown  upon  a  filter  and  washed  with 
distilled  or  rain-water  boiling  hot.  Into  the  clear  filtered  liquor 
which  results  from  all  the  portions  of  water  used  in  the  washing,  a 
little  ammonia  is  added  ;  if  any  precipitate  falls,  it  is  collected  upon 
a  filter  and  washed  :  to  the  new  liquors  obtained  by  this  washing,  a 
solution  of  oxalate  of  ammonia  is  added.  If  there  be  any  lime  pres- 
ent, it  is  thrown  down  in  the  state  of  oxalate,  and  the  liquor,  having 
been  left  at  rest  for  five  or  six  hours,  becomes  completely  clear ;  the 
addition  of  a  few  drops  of  the  solution  of  oxalate  of  ammonia  to  this 
clear  fluid  satisfies  us  whether  the  whole  of  the  lime  has  been  pre- 
cipitated or  not.  The  oxalate  of  lime  is  received  upon  a  filter,  wash- 
ed, and  dried  ;  it  is  then  thrown  into  a  platinum  capsule  along  with 
the  piece  of  filtering  paper  upon  which  it  was  collected,  and  is  heat- 
ed to  a  dull  red,  until  the  paper  of  the  filter  is  completely  consumed 
and  no  further  trace  of  carbon  appears ;  the  capsule  is  then  taken 
from  the  fire  or  from  over  the  spirit  lamp,  and  cooled  ;  when  cold, 
the  matter  which  it  contains  is  moistened  with  a  concentrated  solu- 
tion of  carbonate  of  ammonia. 

The  matter  is  then  dried,  great  care  being  taken  that  nothing  is 
lost  by  particles  flying  out,  and  the  capsule  is  again  heated  to  a  dull 
red  ;  when  cold,  it  is  weighed  accurately,  and  the  quantity  of  matter 
contained  then  becomes  known.  This  matter  is  carbonate  of  lime, 
100  of  which  represent  56.3  of  lime  and  43.7  of  carbonic  acid.  I 
have  said  that  in  arable  soil  other  carbonates  may  be  met  with  be- 
sides that  of  lime ;  calcareous  soils,  for  example,  very  commonly 
contain  carbonate  of  magnesia.  If  we  would  ascertain  the  quantity 
of  this  earth,  the  mode  of  proceeding  which  I  have  just  particularly 

18* 


210  SOIL ITS  ANALYSIS. 

indicated  enables  us  to  do  so  ;  we  have  but  to  evaporate  the  liquit'. 
from  which  the  oxalate  of  lime  was  deposited,  and  then  to  calcine 
the  product  of  the  evaporation  in  a  platinum  capsule.  Any  nitrate 
of  magnesia  which  may  exist  there  will  be  decomposed  at  a  dull  red 
heat,  as  well  as  any  oxalate  of  ammonia  which  may  have  resulted 
from  ammonia  added  in  excess.  By  treating  the  residue  of  the  cal- 
cination with  water  we  obtain  the  magnesia,  which  being  washed. 
has  only  to  be  calcined  and  its  weight  ascertained  by  weighing. 

2d.  If  we  would  be  ;ontent  with  a  simple  approximation,  we  may 
judge  of  the  quantity  oi  calcareous  carbonate  contained  in  a  vegeta- 
ble soil  by  measuring  the  quantity  of  carbonic  acid  which  we  obtain 
from  it.  We  counterpoise  upon  the  scale  of  a  balance  a  phial  con- 
taining some  diluted  nitric  acid ;  we  weigh  a  certain  quantity  of  the 
earth  to  be  analyzed,  and  this  is  added  by  degrees  to  the  acid.  If 
the  earth  contains  carbonates,  effervescence  ensues.  The  liquid  is 
shaken  with  care,  and  having  waited  a  few  minutes  in  order  to  let 
the  carbonic  acid  which  is  mixed  with  the  air  of  the  phial  escape, 
the  phial  with  its  contents  is  again  put  into  the  balance.  If  there 
has  been  no  disengagement  of  carbonic  acid,  it  is  clear  that  to  restore 
the  equilibrium  it  will  be  sufficient  to  add  to  the  opposite  scale  the 
weight  of  the  earth  which  was  put  into  the  phial ;  whatever  is  want- 
ing of  this  weight  represents  precisely  the  weight  of  carbonic  acid 
which  has  been  disengaged.  Presuming  this  acid  to  have  been  com- 
bined with  lime,  the  weight  of  the  calcareous  carbonate  can  be  cal- 
culated exactly. 

Sulphate  of  lime  is  an  occasional  constituent  of  soils ;  to  ascertain 
its  presence  and  quantity,  the  following  is  the  method  of  procedure : 

The  earth  well  pulverized  is  first  roasted  for  a  considerable  time 
in  a  crucible  or  platinum  capsule,  until  all  the  organic  matter  is  com- 
pletely destroyed  ;  it  is  advisable  to  operate  on  about  100  grammes, 
or  about  3.2  ounces  troy  of  soil.  After  this  operation  the  matter  is 
boiled  in  4  or  5  times  its  weight  of  distilled  water  for  some  time  ; 
water  being  added  to  replace  that  which  is  dissipated  by  evaporation ; 
we  then  filter,  re-wash,  and  having  added  all  the  liquors,  we  evapor- 
ate in  a  capsule  until  the  volume  of  the  liquid  is  reduced  to  a  few 
drachms.  To  the  liquid  thus  concentrated  we  add  its  own  bulk  of 
alcohol.  If  the  solution  contains  sulphate  of  lime  it  will  be  deposit- 
ed, and  the  deposite  being  received  upon  a  filter  and  washed  with 
weak  alcohol,  its  weight  is  taken  after  having  been  dried  and  calcined. 
This  salt  is  frequently  seen  deposited  in  the  form  of  fine  colorless 
needles  on  the  cooling  of  the  sufficiently  concentrated  solution  ;  but 
the  addition  of  alcohol  is  always  useful,  because  the  sulphate  of 
lime,  which  is  not  very  soluble  in  water,  is  altogether  insoluble  in 
weak  spirit,  which  on  the  contrary  dissolves  certain  alkaline  and 
earthy  salts  whose  presence  would  interfere  with  the  accuracy  of 
the  result. 

It  may  be  matter  of  great  moment  to  determine  the  existence  and 
the  quantity  of  phosphates  contained  in  a  soil  destined  for  cultiva- 
tion. Although  the  search  for  phosphoric  acid  may  perhaps  require 
a  certain  familiarity  with  chemical  analysis,  I  shall  neverthelest 


SOIL — ITS  ANALYSIS.  211 

indicate  the  method  of  procedure.  It  is  much  to  be  desired  that  en- 
ligfhtened  agriculturists  should  not  remain  strangers  to  manipulations 
of  this  kind. 

The  soil  to  be  analyzed  must  be  first  deprived  of  all  organic  mat- 
ters by  calcination.  After  having  reduced  it  to  a  very  fine  powder 
it  is  to  be  boiled  for  about  an  hour  with  three  or  four  times  its  weight 
of  nitric  or  hydrochloric  acid.  The  solution  is  then  diluted  with 
distilled  water,  and  filtered  ;  the  matter  which  remains  upon  the 
filter  is  generally  silica  or  alumina  which  has  escaped  the  action 
of  the  acid.  After  having  reduced  the  washings  by  evaporation, 
and  added  them  to  the  acid  liquor,  ammonia  in  solution  is  poured 
in.  Taking  the  simplest  instance,  the  precipitate  which  falls  upon 
the  addition  of  this  alkali  may  contain,  1st,  phosphoric  acid  in  union 
with  the  peroxide  of  iron  and  lime  ;  2d.  oxide  of  iron  and  of  man- 
ganese ;  3d.  silica.  This  precipitate,  which  is  usually  of  a  gelatin- 
ous appearance,  is  received  upon  a  filter,  well  washed  and  dried, 
when  the  precipitate  is  readily  detached  from  the  filter.  Tt  is  thrown 
into  a  platinum  capsule  which  is  raised  to  a  white  heat,  after  vi'hich 
the  weight  of  the  residue  is  taken.  The  precipitate  after  calcina- 
tion is  thrown  into  a  small  glass  matrass,  and  dissolved  by  hot  hy- 
drochloric acid.  If  there  is  any  silica  undissolved,  its  quantity  is 
merely  estimated,  if  it  be  very  small ;  if  it  be  a  larger  quantity,  it  is 
to  be  collected  upon  a  filter  and  weighed.  To  the  new  acid  solution, 
about  three  times  its  weight  of  alcohol  is  added :  the  mixture  is 
shaken,  and  pure  sulphuric  acid  is  then  instilled  drop  by  drop  until 
there  is  no  longer  any  precipitate.  The  precipitate  is  sulphate  of 
lime,  which  is  thrown  upon  a  filter,  where  it  is  washed  with  diluted 
alcohol ;  it  is  then  dried,  calcined,  and  the  weight  of  the  sulphate  of 
lime  obtained,  permits  us  to  calculate  that  of  the  lime  which  formed 
part  of  the  precipitate  throv^'n  down  by  the  ammonia  in  the  first  in- 
stance.    100  of  sulphate  of  lime  are  equivalent  to  41.5  of  pure  lime. 

The  alcoholic  liquor  is  concentrated  in  order  to  expel  the  spirit ; 
as  it  is  acid,  it  is  saturated  with  ammonia  until  a  slight  precipitate 
begins  to  be  formed,  which  is  not  redissolved  upon  shaking  the 
mixture.  A  few  drops  of  the  hydrosulphate  of  ammonia  are  then 
added,  upon  which  the  iron  and  the  manganese  fall  in  the  state  of 
sulphurets.  As  a  part  of  the  metals  has  been  precipitated  in  the 
state  of  oxide  by  the  ammonia  added  in  the  hydrosulphate,  it  is  well 
to  digest  for  eight  or  ten  hours,  because  the  hydrosulphate  of  am- 
monia always  ends  by  changing  the  metals  present  into  sulphurets, 
which  being  washed,  dried,  and  reduced  to  the  state  of  oxides  by 
calcination  in  a  platinum  capsule,  are  weighed. 

If  the  first  ammoniacal  precipitate  did  not  contain  phosphoric  acid, 
its  weight  ought  to  be  reproduced  by  adding  that  of  the  lime  to  that 
of  the  metallic  oxides  proceeding  from  the  calcination  of  the  sul- 
phurets. Any  loss  which  is  noted  after  this,  is  due,  if  the  process 
has  been  well  conducted,  to  phosphoric  acid,  which  had  not  been 
collected,  but  which  has  remained  in  the  state  of  phosphate  of  am- 
monia in  the  liquid  treated  by  the  hydrosulphate.  To  determine 
with  precision  the  presence  of  phosphoric  acid,  the  liquid  in  questioj* 


212  SOIL ITS   ANALYSIS. 

must  be  evaporated  to  dryness,  and  the  residue  heated  strongly  in  a 
platinum  capsule.  After  the  dissipation  and  decomposition  of  the 
ammoniacal  salts,  there  remains  watery  phosphoric  acid,  distinguish- 
able by  its  powerful  acid  reaction,  its  sirupy  consistence,  and  its 
fixity. 

By  way  of  example,  I  shall  give  the  results  obtained  in  an  analysis 
of  this  kind : 

From  the  acid  Hquor,  ammonia  threw  down  of :  grs.  troy. 

Ph:)sphates  and  metaliic  oxides          ....  8.012 

These  gave  of  sulphate  of  Ume           ....  8.768 

Equivalent  to  Ume     .         .         .         .         .         .         .  3.612 

Hydrosiilphate  of  ammonia   caused    a   precipitate, 

which,  calcined,  gave  of  metallic  oxides         .         .  1.620 

Lime  and  metallic  oxides  together  .         .         5.233 

Difference  due  to  phosphoric  acid  .         .         2.789 

The  analysis  for  phosphoric  acid  may  be  simplified  by  employing 
a  process  conceived  by  M.  Berthier,  and  which  is  founded  upon  the 
strong  affinity  of  this  acid  for  the  peroxide  of  iron  and  the  insolu- 
bility of  the  phosphate  of  the  peroxide  of  iron  in  dilute  acetic  acid. 
If  to  a  fluid  containing  at  once  phosphoric  acid,  lime,  peroxide  of 
iron,  alumina,  and  magnesia  in  solution,  ammonia  be  added,  the  pre- 
cipitate will  contain  the  whole  of  the  phosphoric  acid.  The  acid 
will  be  in  great  part  combined  in  the  state  of  phosphate  of  iron,  if  the 
peroxide  of  iron  be  in  quantity  more  than  sufficient  to  neutralize  it, 
a  condition  which  must  be  frequently  expected  in  an  arable  soil ; 
however,  to  make  sure  of  this  point  it  is  well  to  add  a  certain  quantity 
of  the  peroxide  of  iron  to  the  soil  which  is  to  be  analyzed.  Besides 
the  phosphate  of  iron,  the  precipitate  may  contain  phosphate  of  lime, 
phosphate  of  alumina,  and  certainly  ammoniacal  magnesian  phos- 
phate. Finally,  with  these  phosphates  will  be  found  associated 
alumina  and  oxide  of  iron,  the  latter  especially  if  it  has  been  intro- 
duced in  excess.  The  precipitate  collected  upon  a  filter  and  wash- 
ed, must  then  be  treated  with  dilute  acetic  acid,  which  will  dissolve 
the  lime,  the  magnesia,  and  the  excess  of  the  oxides  of  iron  and 
alumina,  and  there  will  remain  phosphate  of  iron  or  phosphate  of 
alumina,  because  the  latter  salt  is  as  insoluble  as  the  former  in  acetic 
acid.  Whenever  the  precipitate  in  question,  therefore,  leaves  a 
residue  which  is  insoluble  in  vinegar,  the  presence  of  phosphoric 
acid  may  be  inferred  ;  this  residue  may  consist  of  basic  phosphates 
of  iron  or  alumina,  or  of  a  mixture  of  the  two  salts,  and  no  great 
error  will  be  committed  if  one  hundred  parts  of  this  residue,  calcined, 
be  assumed  as  representing  fifty  of  phosphoric  acid. 

The  presence  of  silica  in  the  precipitate  insoluble  in  acetic  acid 
may,  however,  lead  to  error.  To  make  sure  that  the  precipitate  is 
formed  by  a  phosphate  it  must  be  redissolved  in  hydrochloric  acid, 
and  the  acid  solution  evaporated  to  dryness,  so  as  to  render  the  silica, 
which  may  exist  in  it,  insoluble.  By  treating  the  residue  with  hy 
drochloric  acid  again,  the  phosphates  alone  will  be  dissolved.     Th« 


SOIL — ITS   ANALYSIS.  21$ 

presence  of  phosphoric  acid  may  otherwise  be  determined  by  treat- 
ing the  phosphate  of  iron  in  solution  in  the  way  which  I  have  already 
indicated. 

From  what  precedes,  it  must  be  obvious  that  the  most  carefully 
conducted  chemical  analysis  of  a  soil,  only  leads  us  to  the  discovery 
of  certain  principles  which  exist  in  very  small  quantity,  althoug:i 
their  action  is  unquestionably  useful  to  vegetation.  As  to  the  de- 
termination of  the  relative  quantities  of  sand  and  loam,  this  rests  upon 
simple  washing ;  and  a  chemist  would  spend  his  time  to  very  little 
purpose,  in  seeking  by  means  of  elementary  analyses  to  determine 
the  precise  composition  of  these  substances.  The  finest  part  car- 
ried off  by  the  water  will  always  show  properties  analogous  to  those 
of  clay  ;  the  sand,  which  is  generally  silicious,  will  exhibit  the  char- 
acters of  quartz  ;  and  the  calcareous  fragments,  which  are  mixed 
with  it,  will  exhibit  those  that  belong  to  carbonate  of  lime.  It  will 
be  sufficient  then  in  connection  with  the  mineral  constitution  of  ara- 
ble soils,  to  expose  very  briefly  the  general  properties  of  day  or 
loam,  of  quartz,  and  of  carbonate  of  lime,  substances  in  fact  which 
form  the  bases  of  all  arable  lands.  Pure  clay  composed  of  silica, 
alumina,  and  water,  does  not  contain  these  substances  in  the  state 
of  simple  mixture.  The  inquiries  of  M.  Berthierhave  satisfactorily 
shown  that  clay  is  an  hydrated  silicate  of  alumina.  When  we  re- 
move a  portion  of  the  alumina  from  clay,  for  example,  by  treating  it 
with  a  strong  acid,  the  silica  which  is  set  at  liberty  will  dissolve  in 
an  alkaline  solution,  which  would  not  be  the  case  were  the  silica 
present  in  the  state  of  quartzy  sand,  however  fine. 

Pure  clays  are  white,  unctuous  to  the  touch,  stick  to  the  tongue 
when  dry,  and  when  breathed  upon  give  out  an  odor  which  is  well 
known,  and  is  commonly  spoken  of  as  the  argillaceous  odor.  This 
property  of  dry  clay  to  adhere  to  the  tongue  is  owing  to  its  avidity 
for  water.  It  is  known,  in  fact,  that  dry  clay  brought  into  contact 
with  water,  first  swells,  and  finally  mixes  with  it  completely.  Duly 
moistened  it  forms  a  tough  and  eminently  plastic  mass.  Exposed 
to  the  air,  moist  clay,  as  it  dries,  shrinks  considerably ;  and  if  the 
drying  be  rapid,  the  mass  cracks  in  all  directions.  It  is  to  an  action 
of  this  kind  that  we  must  ascribe  the  cracks  and  deep  fissures  which 
traverse  our  clayey  soils  in  all  directions  during  the  continuance  of 
great  droughts. 

The  constitutional  water  of  clays  is  retained  by  a  very  powerful 
affinity,  and  does  not  separate  under  a  red  heat ;  pure  clay  has  a 
specific  gravity  of  about  2.5;  but  the  weight  is  frequently  modified 
by  the  presence  of  foreign  matter,  for  it  contains  sand,  met»Hic 
oxides,  carbonate  of  lime,  carbonate  of  magnesia,  and  frequently 
even  combustible  substances  from  bitumen  to  plumbago,  all  of  which 
admixtures  of  course  modify  the  properties  which  are  most  highly 
esteemed  in  clays,  such  as  fineness,  whiteness,  infusibility,  &c. 

Quartz  is  abundantly  distributed  throughout  nature,  and  is  met 
with  in  very  difl^erent  states  in  the  form  of  transparent  colorless 
crysiais  constituting  rock  crystals,  as  sand  of  different  fineness; 
finally,  in  masses  constituting  true  rocks.     Quartz  is  the  silica  of 


214  SOIL ITS   ANALYSIS. 

chemists,  and  a  compound,  according  to  them,  of  oxygen  and  siliconi 
in  the  proportion,  Berzelius  says,  of  100  of  the  radical  to  108  of 
oxygen. 

Silica  in  a  state  of  purity  occurs  in  the  form  of  a  white  powder, 
and  having  a  density  of  2.7.  It  is  infusible  in  the  most  violent  fur- 
nace, but  it  not  only  melts  in  the  intense  heat  which  results  from  the 
combustion  of  a  mixture  of  hydrogen  and  oxygen  gas,  but  it  is  even 
dissipated  in  vapor.  As  generally  obtained,  silica  is  held  insoluble 
in  water;  still,  when  in  a  state  of  extreme  subdivision,  it  is  s«)luble  ; 
and  then  its  insolubility  is  probably  not  so  absolute  as  is  generally 
supposed,  for  M,  Payen  has  found  notable  quantities  in  the  water  of 
the  Artesian  well  of  Grenelle,  and  in  that  of  the  Seine.  Silica  ex- 
ists especially  in  very  appreciable  quantity  in  certain  hot  springs 
where  the  presence  of  an  alkaline  substance  favors  its  solution  ; 
the  water  of  the  hot  springs  of  Reikum  in  Iceland  contain  about 
Y75^oth  parts  of  its  weight  of  silica ;  and  the  thermal  spring  of  Las 
Trincheras,  near  Puerto  Cabello,  deposites  abundant  silicious  concre- 
tions. The  water  of  this  latter  spring,  which  is  at  the  temperature 
of  210°  F.,  besides  silica  contains  a  quantity  of  sulphurated  hydro- 
gen gas,  and  traces  of  nitrogen  gas.  Rock  crystal  when  colorless 
and  transparent  may  be  regarded  as  pure  silica ;  in  the  varieties  of 
quartz  which  mineralogists  designate  as  chalcedony,  agate,  opal,  &c., 
the  silica  is  combined  with  different  mineral  substances,  particularly 
oxide  of  iron  and  of  manganese,  alumina,  lime,  and  water. 

Carbonate  of  lime,  considered  as  rock,  belongs  to  every  epoch  in 
the  geological  series,  and  frequently  constitutes  extensive  masses. 
When  pure  it  is  composed  of  lime  56.3,  carbonic  acid  43.7 ;  and  its 
density  is  then  from  2.7  to  2.9.  It  dissolves  with  etfervescence 
without  leaving  any  residue  in  hydrochloric  or  nitric  acid.  Exposed 
to  a  red  heat  its  acid  is  disengaged,  and  quick-lime  remains.  Car- 
bonate of  lime  is  insoluble  in  water,  but  it  dissolves  in  very  consid- 
erable quantity  under  the  influence  of  carbonic  acid  gas.  When 
such  a  solution  is  exposed  to  the  air  the  acid  escapes  by  degrees, 
and  the  carbonate  is  deposited,  by  which  means  those  numerous 
deposites  of  carbonate  of  lime  are  produced,  which  we  see  constitu- 
ting tufas  and  stalactites.  The  solubility  of  carbonate  of  lime  in 
water  acidulated  with  carbonic  acid,  enables  us  to  understand  how 
plants  should  meet  with  this  salt  in  the  soil,  inasmuch  as  rain-water 
always  contains  a  little  carbonic  acid. 

The  mineral  substances  which  we  have  now  studied,  taken  iso- 
latedly,  would  form  an  almost  barren  soil  ;  but  by  mixing  them  witii 
discretion  a  soil  would  be  obtained,  presenting  all  the  essential  con- 
ditions of  fertility,  which  depend  as  it  would  seem  much  less  on  the 
chemical  constitution  of  the  elements  of  the  soil  than  on  their  physi- 
cal properties,  such  as  their  faculty  of  imbibition,  their  density,  their 
power  of  conducting  heat,  &c.  It  is  unquestionably  by  studying 
these  various  properties  that  we  come  to  form  a  precise  idea  of  the 
causes  which  secure  or  exclude  the  qualities  we  require  in  arable 
poiis.     This  has  been  done  very  ably  by  M.  Schiibler,  and  his  admj- 


SPECIFIC    GRAVITY  OF    SOIL.  215 

rable  paper  will  remain  a  model  of  one  application  of  the  sciences 
to  agriculture.* 

The  researches  of  M.  Schiibler  were  directed  to  the  mineral  sub- 
stances vvhich  are  generally  found  in  soils,  viz  :  1st.  silicious  sand; 
2d.  calcareous  sand  ;  3d.  a  sanely  clay  containing  about  y^^ths  of 
sand  ;  4th.  a  strong  clay  containing  no  more  than  about  f^nl'hs  of 
sand  ;  5th.  a  still  stronger  clay  containing  no  more  than  about  ,-\^th 
of  sand ;  6th.  nearly  pure  clay  ;  7th.  chalk,  or  carbonate  of  lime  in 
the  pulverulent  state  ;  8th.  humus ;  9th.  gypsum  ;  10th.  light  gar- 
den earth,  black,  friable,  and  fertile,  and  containing,  in  100  parts, 
clay  52.4,  quartzy  sand  36.5,  calcareous  sand  1.8,  calcareous  earth 
2.0,  humus  7.3  ;  Uth.  an  arable  soil  composed  of  clay  51.2,  silicious 
sand  42.7,  calcareous  sand  0.4,  calcareous  earth  2.3,  humus  3.4 ; 
and  12th.  an  arable  soil  taken  from  a  valley  near  the  Jura,  contain- 
ing clay  33.3,  silicious  sand  63.0,  calcareous  sand  1.2,  calcareous 
earth  and  humus  1.2,  loss  1.3. 

The  object  of  these  inquiries  was  to  ascertain,  1st.  the  specific 
gravity  of  soils ;  2d.  their  power  of  retaining  water  ;  3d.  their 
consistency ;  4th.  their  aptitude  to  dry  ;  5th,  their  disposition  to 
contract  while  drying ;  6th.  their  hygrometric  force ;  7th.  their 
power  of  absorbing  oxygen ;  8th.  their  faculty  of  retaining  heat ; 
and  9th.  their  capacity  to  acquire  temperature  when  exposed  to  the 
sun's  rays. 

Specific  gravity  of  soils.  The  weight  of  soils  may  be  compared 
in  the  dry  and  pulverulent  state,  or  in  the  humid  state,  or  the  spe- 
cific gravity  of  the  particles  which  enter  into  their  composition  may 
be  determined.  This  last  information  is  easily  obtained  by  the  fol- 
lowing method  :  take  a  common  ground  stopper  bottle,  weigh  it 
stoppered  and  full  of  distilled  water  ;  let  it  then  be  emptied,  in  order 
that  a  known  quantity  of  the  soil,  in  the  state  of  powder  and  quite 
dry,  may  be  introduced  into  it.  A  quantity  of  water  is  now  poured 
in,  and  the  phial  is  shaken  to  secure  the  disengagement  of  all  air 
bubbles ;  the  phial  is  then  filled  with  distilled  water,  and  when  the 
upper  part  has  become  clear  the  stopper  is  replaced  ;  the  phial  is 
then  wiped  dry  and  weighed  again.  The  difference  between  the 
weight  of  the  phial  full  of  water  plus  that  of  the  matter,  and  the 
weight  of  the  phial  containing  the  matter  and  the  water  mixed,  gives 
the  weight  of  the  water  displaced  by  this  matter.     Thus  : 

Weight  of  the  phial  full  of  water 60.0 

Weight  of  the  matter ••24.0 

84.0 

Weight  of  the  phial  containing  the  mingled  earth  and  water  — 74.4 
Difference  of  water  displaced 9.6 

which  is  the  weight  of  the  volume  of  water  equal  to  that  of  the 
matter  introduced  into  the  phial ;  we  have  consequently  for  the  spe- 
cific gravity  of  the  earth  ^-:|=2.5,  the  weight  of  the  water  having 
)}een  taken  as  1. 

•  SIchiibler,  Annals  of  French  Agriculture,  vol.  xl.  p.  122,  2d  sories. 


216  IMBIBING   POWERS   OF   SOIL. 

ThU  number  represents  the  mean  specific  gravity  of  the  isolatea 
particles  of  the  powder  which  has  been  examined.  J3ut  we  must 
not  from  this  density  pretend  to  deduce  the  weight  of  a  particular 
volume  of  soil,  a  cubic  foot  or  a  cubic  yard,  for  instance  ;  we  should 
come  to  far  too  high  a  number.  The  weight  of  a  given  volume  of 
earth  must  be  determined  immediately  by  ramming  it  into  a  mould 
or  measure  of  a  known  capacity. 

From  M.  Schiibler's  experiments  it  appears,  1st.  that  silicious 
and  calcareous  sandy  soils  are  the  heaviest  of  any  ;  2d.  that  clayey 
soils  are  of  least  density  ;  3d.  that  humus  or  mould  is  of  much 
lower  density  than  cl^y  ;  4th.  that  a  compound  soil  being  generally 
by  so  much  the  heavier  as  it  contains  a  larger  proportion  of  sand, 
and  so  much  the  lighter  as  it  contains  a  larger  quantity  of  clay,  of 
calcareous  earth,  and  of  humus,  it  is  possible  from  the  density  of  a 
soil  to  infer  the  nature  of  the  principles  which  prevail  in  it.  In  the 
course  of  his  experiments  M.  Schiibler  found  that  artificial  mixtures 
always  gave  higher  densities  than  those  that  ought  to  have  resulted 
from  the-  several  densities  of  each  of  the  sorts  of  substance  which 
formed  the  mixture. 

Imbibition  of  water.  The  power  which  soils  possess  of  retaining 
water  or  of  resisting  the  too  rapid  dissipation  of  their  moisture,  is 
highly  important  in  its  influence  upon  their  fertility.  This  faculty 
is  measured  comparatively  in  the  following  manner  :  a  given  quan- 
tity of  soil  is  taken,  say  from  3  to  400  grains  ;  it  is  dried  until  it 
ceases  to  lose  weight ;  it  is  then  made  into  a  thin  paste  and  thrown 
upon  a  moistened  filter  ;  when  it  has  ceased  to  drop  it  is  weighed. 
The  increase  of  weight  is  plainly  due  to  the  quantity  of  water  re- 
tained by  the  soil,  thus  : 

Weight  of  the  dry  soil 300.0 

Weight  of  the  moistened  filter •  •  75.0 

375.0 

Weight  of  the  filter  and  moistened  earth ••525 

Water  absorbed 150 

In  the  experiment  quoted,  100  of  dry  earth  absorbed  or  imbibed 
60  of  water.  The  following  table  contains  the  result  of  experi- 
ments made  on  the  imbibing  power  of  diflferent  soils. 

Water  absorbed  by 
'  Kind  of  earth.  100  parts  of  the  earth. 

Silicious  sand • 25 

Gypsum 27 

Calcareous  sand 29 

Sandy  clay 40 

Strong  clay 50 

Sandy  clay 70 

Fine  calcareous  earth 85    ^ 

Humus 190 

Garden  earth 89 

An  arable  soil 5£ 

Another  arable  soil 48 

It  appears,  therefore,  that  the  silicious  and  calcareous  soils  and 
the  gypsum  have  the  least  affinity  for  water  ;  the  clayey  soil  re- 
tained by  so  much  the  more  as  it  contained  a  smaller  quantity  of 
sand  ;  the  fine  calcareous  earth  retained  15  per  cent,  more  than  the 


I 


CONSISTENCY   OF  SOIL.  217 

pure  clay ;  while  the  calcareous  sand  retained  41  per  cent.  less. 
This  fact  proves  how  much  the  state  of  suhdivision  must  influence 
the  physical  properties  of  soils;  and  it  is  easily  to  be  understood 
that  in  noting  the  presence  of  calcareous  matter  in  an  arable  soil 
■we  are  carefully  to  indicate  the  form  and  degree  of  subdivision  in 
which  it  occurs  ;  humus,  however,  is  the  substance  which  shows 
itself  most  greedy  of  moisture,  and  we  perceive  from  this  fact  where- 
fore soils  rich  in  this  principle  have  so  strong  an  affinity  for  water. 

Consistence,  tenacity,  friability  of  soils.  The  consistence  or 
tenacity  of  soils  is  an  important  property  which  agriculturists  indi- 
cate when  they  speak  of  soils  being  strong  or  stiff,  and  light,  the 
amount  of  power  expended  in  ploughing  being  taken  as  a  measure 
of  these  qualities.  To  compare  different  soils  under  the  point  of 
view  of  their  tenacity  in  the  dry  state,  M.  Schiibler  moulded  various 
kinds,  duly  moistened,  into  equal  and  similar  parallelopipeds. 
When  these  solids  were  completely  dry,  he  placed  either  extremity 
upon  a  fixed  support,  and  by  means  of  the  scale  of  a  balance  hung 
exactly  from  the  middle  of  the  prisms,  he  added  weights  gradually 
until  they  gave  way ;  the  weight,  supported  by  each  parallel opiped 
immediately  before  it  broke,  expressed  its  tenacity. 

In  working  x  damp  soil  we  have  not  only  to  overcome  its  force  of 
cohesion,  but  further  and  principally  to  get  the  better  of  its  adhesion 
to  our  implements.  This  consideration  led  M.  Schiibler  to  estimate, 
always  comparatively,  the  power  which  it  is  necessary  to  expend  in 
working  soils  of  different  descriptions.  As  the  material  which 
enters  into  the  construction  of  agricultural  instruments  is  in  general 
iron  and  wood,  he  did  no  more  than  ascertain  the  disposition  of  the 
soil  to  adhere  to  these  two  substances.  In  the  experiments,  the 
results  of  which  we  shall  immediately  detail,  two  discs  were  employ- 
ed, one  of  iron,  the  other  of  beech-wood,  having  equal  surfaces. 
The  disc  was  connected  with  the  extremity  of  the  arm  of  a  very 
delicate  balance  ;  it  was  then  brought  into  perfect  contact  with  the 
moist  soil,  and  when  it  adhered,  the  opposite  scale  of  the  balance  was 
loaded  until  the  adhesion  was  overcome.  In  experiments  of  this 
kind  it  is  obviously  indispensable  that  the  soil  in  each  instance  should 
have  the  same  degree  of  humidity;  they  were  tried,  consequently, 
at  the  point  of  saturation  with  water. 

Pure  dry  clay  possessed  the  greatest  tenacity,  and  its  power  was 
expressed  by  the  number  100 ;  the  tenacity  possessed  by  other  mat- 
ters was  then  compared  to  that  of  pure  clay.  The  following  table 
exhibits  the  results  of  the  two  series  of  experiments,  viz.  those 
having  reference  to  the  tenacity  and  those  having  reference  to  the 
farce  of  cohesion. 

10 


218 


TENACITY  OF  SOIL. 


Kind  of  ••il. 

TiMCity    of  «oiI, 

that  of  pure  clay 

bein^  100. 

Tenacity  express- 
ed iu  weight. 

Ccfie«ion  in  the 
mcisi  stale. 

Verticil  adhecioB 

to     iran    and    to 

wood  en  a  aurfa»« 

ofS.93r8quar« 

inches. 

Silicious  sand 

Calcareous  sand 

Fine  calcareous  earths 
Gypsum 

0 
0. 
5.0 
7.3 
8.7 
57.3 
68.8 
83.3 
100.0 
7.6 
33.0 
22.0 

kil. 
0. 
0. 

0.55 
0.81 
0.97 
6.36 
7.64 
9.25 
11.10 
0.84 
3.66 
2.44 

kil. 
0.17 
0.19 
0.65 
0.49 
0.40 
0.35 
0.48 
0.78 
1.22 
0.29 
0.26 

kil.« 
0.19 
0.20 
0.71 
0.53 
0.42 
0.40 
0.52 
0.86 
1.32 
0.34 
0.28 
0.27 

Stiff  clayey  soil 

Garden  earth 

Earth  from  Hoffwyll  . . 
Earth  from  the  Jura . . 

M.  Schiibler  finds,  from  his  experiments,  that  a  dry  soil  is  very 
easily  worked  vi^hen  its  tenacity  does  not  exceed  10,  that  of  pure 
clay  being  100  in  the  moist  state.  Soils  are  further  worked  with 
ease  when  their  adherence  to  a  surface  3.937  inches  square  is  re- 
presented by  a  weight  of  from  0.15  to  0.30  kil. ;  i.  e.  from  0.380  to 
0.760,  or  nearly  ^d  to  |ths  of  a  lb.  avoird.  ;  the  latter  term  passed, 
the  difliculty  of  working  increases  rapidly,  and  a  very  considerable 
force  is  required  when  the  adherence  to  the  same  surface  amounts 
to  0.70  kil.  or  1  840  lbs.  avoird. 

The  tenacity  of  a  wet  soil  is  not,  however,  in  the  direct  ratio  of 
its  faculty  of  imbibition.  Loams  and  loose  calcareous  soils,  which 
absorb  much  more  water  than  clay,  are  nevertheless  much  less  tena- 
cious ;  and  then  water  actually  makes  sandy  soils  stiffer  than  they 
are  when  dry. 

Every  practical  farmer  knows  how  much  more  friable  stiff  wet 
soils  become  from  the  effects  of  frost.  The  water  in  expanding  as 
it  becomes  solid  pushes  apart  the  molecules  of  the  soil,  and  it  is  to 
this  action  that  the  advantages  of  autumn  ploughing  are  with  justice 
ascribed.  M.  Schiibler  found  that  the  cohesion  of  a  stiff  clay  which 
was  equal  to  68  fell  to  45,  when  before  it  was  tried  the  clay  was 
exposed  to  the  frost. 

Disposition  of  the  soil  to  become  dry.  The  faculty  of  throwing 
off  by  evaporation  any  excess  of  water  with  which  it  may  be  charg- 
ed, is  as  essential  to  constitute  a  good  soil  as  is  that  of  retaining 
moisture  in  due  proportions.  Those  soils  which  throw  off  too  slow 
ly  the  excess  of  moisture  they  have  acquired  during  the  winter 
occasion  much  trouble  to  the  husbandman.  They  are  perfect]y  un- 
workable in  the  spring,  and  consequently  can  only  be  sown  veiy 
4ate.  M.  Schiibler  tried  the  retentive  powers  of  the  soil  by  the 
following  method.  A  metallic  disc,  furnished  with  a  narrow  rim. 
was  suspended  to  the  «m  of  a  balance.     Over  this  disc,  the  soil  tc 

*  The  abbreviate  kil.  In  the  above  table  signifies  killogramme,  a  weight  equal  to  2.S 
lbs.  avoirdupois.  As  the  weights  are  principally  interesting  in  their  relations  lo  90* 
aootber,  it  has  not  been  thought  necessary  to  reduce  them  to  English  weights. 


SHRINKING  OF  SOILS.  219 

be  tried  and  previously  brought  to  the  point  of  saturation  with  moist- 
ure,  was  spread  as  evenly  as  possible.  The  weight  of  the  disc 
thus  charged  was  noted,  and  it  was  weighed  anew,  after  having 
been  kept  for  four  hours  in  a  temperature  of  18.75°  cent.  (65.75^ 
Fahr.)  The  weight  of  the  water  lost  by  evaporation  was  obtained 
by  a  second  weighing;  the  complete  desiccation  of  the  soil  was  then 
completed  in  the  stove.  The  following  is  the  detail  of  one  opera- 
tion : 

Weight  of  the  moist  earth 310 

Weight  after  four  hours'  exposure  to  the  air 260 

Water  evaporated 50 

Weight  of  the  moist  earth 310 

Weight  after  complete  desiccation 200 

Whole  quantity  of  water  contained  in  the  soil  tried  ...  110 

Thus  100  of  water  of  imbibition  lost  45.5  during  exposure  to  the 
air  for  4  hours  at  a  temperature  of  about  66°  Fahr.  A  more  se- 
verely accurate  method  might  readily  be  contrived,  but  that  employ- 
ed by  M.  Schiibler  appears  sufficient  for  ordinary  purposes.  His 
results,  in  regard  to  the  different  kinds  of  soil  he  tried,  are  these : 

100  parts  of  (he  water 
contained  in  the  soil  lose 
Kinds  of  soil.  in  the  course  of  4  hours 

at  66  deor.  Fahr. 

Silicioussand  88.4 

Calcareous  sand 75.9 

Gypsum 71.7 

Sandy  clay 52.0 

Stiffish  clay 45.7 

Stitfclay •.  34.9 

P'ueclay 31.9 

Calcareous  soil 28.0 

Humus 20.5 

Garden  earth 24.3 

Arable  soil  of  Hoffwyll 32.0 

Arable  soil  of  the  Jura 40.1 

Of  all  the  substances  examined,  sand  and  gypsum  are  obviously 
those  which  allow  the  water  to  pass  off  most  rapidly  by  evaporation. 
The  calcareous  or  chalky  soil  again  has  a  high  retentive  power ; 
but  it  varies  much  in  different  instances,  apparently  in  consequence 
of  different  degrees  of  fineness  ;  it  is  however  surpassed  by  humus, 
and  the  garden  soil  which  was  tried.  Humus  is  therefore  at  the 
head  of  the  list  of  substances  in  reference  to  retentive  properties. 

All  soils  shrink  more  or  less  in  drying,  and  form  cracks,  in  the 
way  already  indicated ;  the  shrinking  has  been  estimated  by  means 
of  prisms  of  soils  measured  in  the  moist  state,  and  after  being  dried 
in  the  shade  : 

Kinds  of  soil.  100  parts  cube 

shrink  to. 

Carbonate  of  lime  in  fine  powder 950 

Sandy  clay   940 

Stiffish  clay 911 

Stiff  clay 886 

Pure  clay   817 

Humus 846 

Garden  earth 851 

Arable  soil  of  Hoffwyll 880 

Arable  soil  of  Jura 90S 


220 


UYGROMETRIC  POWER  OF  SOILS. 


Gypsum,  silicions,  and  calcareous  siiid  do  not  appeal  in  this  table, 
because  they  do  not  shrink  in  drying  The  humus  appears  to  have 
shrunk  the  most ;  and  dry  humus  is  liable  to  swell  in  the  same  pro- 
portion when  it  is  moistened.  This  property  explains  the  obvious 
elevation  of  certain  turfy  or  mossy  soils  at  the  period  of  the  rains. 

Hygromelric  property  of  soils.  Agriculturists  allow,  that  those 
soils  which  have  the  property  of  attracting  moisture  from  the  atmo- 
sphere are  generally  among  the  most  fertile.  This  hygiometric 
property  must  not  be  confounded  with  that  in  virtue  of  which  moist- 
ure is  retained.  It  appears  to  depend  especially  on  the  porousness 
of  a  soil,  and,  probably,  also,  in  soi  le  degree,  on  the  deliquescent 
salts  which  it  contains,  even  in  veiy  small  quantity.  Davy  was 
disposed  to  regard  the  hygrometric  property  of  soils  as  a  certain 
index  of  their  good  quality  ;  and  the  experiments  of  M.  Schiibler 
upon  the  point,  all  tend  to  confirm  the  accuracy  of  this  view.  In 
M.  Schiibler's  experiments,  the  increase  of  weight  of  dry  soils  was 
ascertained  by  exposing  them  for  a  certain  time  in  an  atmosphere 
kept  at  the  point  of  saturation  with  moisture,  and  at  the  same  tem- 
perature, between  60°  and  65°  Fahr. 


Kind  of  soil. 

500  centigrammes,  or  77.165  grains  troy,  of  soil,  spread 

upon  a  surface  of  36,000   millimetres,    or    141.48   square 

inches,  absorbed  in— 

12  hours. 

24  hours. 

48  hours. 

72  hours. 

Grains. 

0 
.154 

0.077 
1.617 
1.925 
2.310 
2.849 
2.002 
6.160 
2.695 
1.232 
1.078 

Grains. 

0 

.231 
0.077 
2.002 
2.310 
2.772 
3.234 
2.387 
7.469 
3.465 
1.771 
1.463 

Grains. 

0 

.231 
0.077 
2.156 
2.618 
3.080 
3.696 
2.695 
8.470 
3.850 
1.771 
1.540 

Graius. 

0 

.231 
0.077 
2.156 
2.695 
3.157 
3.773 
2.695 
9.240 
4.004 
1.771 
1.540 

Gypsum  • 

I.iorht  rliv.....». . 

Chalky  soil  in  fine  powdei 

Arable  soil  of  Hoffwyll  . . . 
Arable  soil  of  Jura 

From  the  results  comprised  in  the  preceding  table,  we  may  con- 
clude, first,  that  the  faculty  of  absorbing  lessens  as  soils  acquire 
moisture;  second,  that  humus  is  the  most  hygrometric  of  all  the 
substances  examined  ;  third,  that  the  clays  which. absorb  the  largest 
quantity  of  moisture  are  those  which  contain  the  smallest  proportion 
of  .sand  ;  and  fourth,  that  silicious  sand  and  gypsum  do  not  absorb 
moisture  in  any  appreciable  quantity. 

Ahsorptum  of  oxygen  gas  hy  arable  soils.  Humboldt  had  already 
observed,  before  the  year  1793,  that  argillaceous  soils,  the  lydian 
stone,  certain  schists,  and  humus,  deprived  the  air  of  its  oxygen. 
He  had  also  observed  that  the  sides  of  the  large  cavities  dug  in  the 
salt  mines  of  Saltzburg,  absorbed  this  gas,  and  thus  rendered  the 
stagnant  atmosphere  of  the  virorkings  irrespirable  and  incapable  of 
supporting  combustion.     Finally,  this  illustrious  observer  had  satis 


ABSORPTION  OF  OXYGEN  BY  SOILS.  221 

factorily  ascertained,  at  the  same  period,  that  earth  taken  from  the 
galleries  of  these  mines,  only  became  fertile  after  having  been  ex- 
posed to  the  atmosphere  for  a  considerable  length  of  time.  I  have 
quoted  these  curious  observations  because  they  are,  so  far  as  I  know, 
the  first  udiich  established  the  necessity  of  the  presence  of  oxygen 
in  the  interstices  of  the  soil,  or,  as  M.  Humboldt  then  said  and,  in- 
deed, as  may  still  be  maintained,  the  utility  of  a  previous  oxidation 
of  the  soil. 

All  our  agricultural  facts,  indeed,  confirm  this  view  of  the  necessity 
of  air  in  the  interstices  of  the  soil  that  is  destined  for  the  growth  of 
vegetables.  When,  by  ploughing  very  deeply,  for  example,  we 
bring  up  a  portion  of  the  subsoil  into  the  arable  layer,  in  order  to  in- 
crease its  thickness,  we  always  lessen  the  fertility  of  the  ground  for 
a  time  ;  in  spite  of  the  action  of  manures,  and  of  any  treatment  we 
may  adopt,  a  certain  time  must  elapse  before  the  subsoil  can  pro- 
duce an  advantageous  effect ;  it  is  absolutely  necessary  that  it  have 
been  exposed  to  the  atmospheric  influences,  and  it  is  then  only  that 
deep  ploughing,  which  gives  the  arable  layer  a  greater  thickness, 
pays  completely  for  the  expense  it  has  occasioned. 

I  am  disposed  to  ascribe  the  absorption  of  oxygen  gas  by  clayey 
soils,  to  the  oxide  of  iron,  which  they  almost  always  contain,  and 
which  is  in  the  minimum  state  of  oxidation,  when  the  clay  lies  at  a 
certain  depth.  In  the  performance  of  some  soundings  in  a  tertiary 
soil  of  the  department  of  the  lower  Rhine,  which  I  performed  in 
1822,  I  had  occasion  to  observe  that  the  clays  brought  up  white  by 
the  borer,  very  speedily  became  blue  by  exposure  to  the  air;  and 
that  in  gaining  color  they  condensed  oxygen.  I  propose  returning 
upon  this  fact  to  shovi^  the  important  part  which  this  simple  super- 
oxidation  probably  plays  in  the  amelioration  of  soils.* 

M.  Schiibler,  again,  has  studied  the  action  of  oxygen  gas  upon  the 
component  parts  of  arable  soils,  and,  according  to  him,  the  absorp- 
tion of  this  gas  cannot  be  doubted  ;  it  is  very  trifling  in  connection 
with  sand  and  gypsum,  very  decided  as  regards  clay,  loam,  and 
humus.  As  M.  de  Humboldt  and  M.  de  Saussure  had  already  done, 
M.  Schiibler  observed  humus  to  change  a  portion  of  the  oxygen 
which  it  fixed,  into  carbonic  acid ;  but,  in  general,  the  other  sub- 
stances, or  soils,  or  elements  of  soils,  upon  which  he  experimented, 
appeared  to  absorb  the  oxygen  by  the  intermedium  of  the  protoxide 
of  iron,  from  which  they  are  never  altogether  free.  Besides  this 
cause,  due  to  the  superoxidation  of  a  metal,  M.  Schiibler  thinks  that 
a  certain  portion  of  the  oxygen  disappears  by  condensation  within 
the  pores  of  some  soils ;  and  in  support  of  his  opinion  he  appeals  to 
the  admirable  observations  of  M.  de  Saussure,  on  the  condensation 
of  the  gases  by  porous  bodies.  Starting  from  the  fact  that  the  roots 
of  plants   require   the  presence  of  oxygen  in  order  to  thrive,  he 

*  Austin  proved,  that  during  the  oxidation  of  metallic  iron  under  water,  there  is  a 
constant  production  of  ammonia.  Certain  experiments  commenced  some  time  ago,  and 
wliich  I  still  continue,  will  establish  in  the  most  precise  manner,  as  I  hope,  the  fact 
liiat  this  formation  of  ammonia  likewise  takes  place  during  the  passage  of  the  protox- 
ide of  iron  to  the  state  of  hydrated  peroxide.  The  theoretical  conclusions  deducibl« 
from  this  fact,  and  the  economic  applications  which  may  tlow  from  it,  mXist  be  obvious. 

19* 


£23 


CAPACITY  OF  SOILS  FOR  HEAT. 


ascribes  a  greater  power  to  the  gases  compressed  or  condensed 
within  the  interstices  of  the  soil.  But  the  action  of  the  air  upon  ihe 
roots  of  vegetables  is  readily  conceivable  in  soils  of  a  h)ose  nature, 
especially  if  ihcy  have  been  sufficiently  worked,  without  the  necessity 
of  having  recourse  to  such  an  explanation. 

Capacity  of  soUs  for  heat.  The  quantity  of  heat  which  a  soil  will 
receive,  retain,  or  throw  off  in  a  given  time,  depends  upon  the  con- 
ducting power  which  it  possesses.  M.  Schiibler  endeavored  to 
measure  this  power  comparatively  by  measuring  the  rates  of  cooling. 
In  a  vessel  of  the  capacity  of  595  cubic  centimetres,  or  234.2  cubic 
inches,  filled  with  the  substance  to  be  tried,  a  thermometer  was 
placed,  with  its  bulb  in  the  centre.  The  temperature  having  been 
brought  up  to  62.5°  C,  (144.5°  Fahr.,)  the  time  was  noted  which 
each  substance  required  to  fall  to  21.2°  C,  or  about  70°  Fahr.,  the 
temperature  of  the  surrounding  air  being  16.2°  C,  or  about  61'  Fahr. 


Kindofsofl. 

Power  of  retaining  heat, 
that  of  calcareous  sand 
beinff  100. 

Time  which  234.2  cubic 
inches   of  soil  required 
to  cool  from  141=  to  70  = 
Fahr.,  the    temperature 
of  the   surroundin'  air 
being  about  61  o   jPahr. 

r!»lrarpnn«i  «sinH 

100.0 
95.6 
73.2 
76.9 
71.1 
68.4 
6C.7 
61.8 
49.0 
64.8 
70.1 
74.3 

h.  ra. 
3.30 
3.27 
2.34 
2.41 
2.30 
2.24 
2.19 
2.10 
1.43 
2.16 
2.27 
0.36 

Rnnilv"  rlav 

Rtiffish  rlav 

ArAblesoilofHoffwyil... 
Arable  soil  of  the  Jura.  ••  • 

The  general  observations  which  these  experiments  suggest,  are 
that,  for  equal  volumes,  calcareous  or  silicious  sand  possesses  greater 
powers  of  retaining  heat  than  any  of  the  other  substances  tried. 
This  fact  explains  the  high  temperature  and  the  dryness  which 
sandy  soils  maintain  even  during  the  night  in  summer.  Humus  is 
obviously  the  substance  which  possesses  the  highest  conducting 
powers. 

Degrees  in  which  soils  become  heated  under  exposure  to  the  sun. 
There  is  no  one  who  has  not  had  occasion  to  observe  the  high  tem- 
perature which  bodies  acquire  when  exposed  to  the  rays  of  the 
bright  sun.  There  are  some,  such  as  dry  sand,  slates,  and  certain 
colored  rocks,  which  become  burning  hot.  It  is  by  the  heat  of  the 
sun  that  the  soil,  before  it  is  shaded  by  the  leaves  and  stems  of  plants, 
rises  in  temperature,  and  throws  off  the  excess  of  moisture  which  it 
had  imbibed  in  the  winter.  Agriculturists  all  know  how  different 
the  degree  in  which  this  heating  takes  place,  even  in  soils  that  are 
close  to  one  another.  A  light-colored,  moist,  clayey  soil  will  heat 
giucb  less  thaa  a  dajk-colored,  calcareous,  or  sandy  soil.     The  dif 


CLASSIFICATION  OF  SOILS. 


lercnces  in  the  heat  acquired  in  various  soils  depend,  1st,  on  the 
state  of  their  surface  ;  2d,  on  iheir  composition  ;  3d,  on  the  quantity 
of  water  which  they  contain  ;  and,  4th,  on  the  anjrle  of  incidence  of 
the  sun's  rays.  M.  Schiibler,  by  a  method  which  is  far  from  being 
unobjectionable,  but  which  may  be  excused,  considering  the  diffi- 
cuhies  of  the  subject,  measured  the  temperature  acquired  by  different 
soils  exposed  to  the  sun  for  the  same  length  of  time,  and  in  circum- 
stances as  nearly  alike  as  possible  ;  the  numbers  obtained  are  given 
in  the  following  table  : 


Soils 


Silicious  sand,  yellowish  gray  •  •  • 

Calcareous  sand,  whitish  gray 

Bright  gypsum,  whitish  gray 

Poorcliy,  yellowish  ....  • 

Stiff  clay 

Argillaceous  earth,  yellowish  gray 

Pure  clay,  bluish  gray 

Calcareous  earth,  white 

Humus,  blackish  gray 

Garden  earth,  blackish  gray 

Arable  earth  of  Hoffwyll,gray.... 
Arable  earth  of  the  Jura,  gray 


Highest  temperature  acquired  by  the  upper 
layer,  the  mean  tempernture  of  tbe  atmo- 
sphere being  25°  C.  (77=  F.) 


The  soil  moist,  de- 

The soil  dry,  de- 

grees centigrade. 

grees  centigrade. 

37.25  (99°  F.) 

44.75  (112  =  . 5  F.) 

37.38 

44.. 50 

3G.25 

43.62 

36.75 

44.12 

.37.25 

44.50 

37.38 

44.62 

37.50 

45.00 

35.63  (96°. IF.) 

43.00  (109».4F.) 

39.75  (103».5F.) 

47.37 

37.50 

45.25 

36.88 

44.25 

36.50 

43.75 

In  comparing  the  circumstances  which  concur  in  assisting  the 
action  of  the  sun's  rays  in  raising  the  temperature  of  the  soil,  it 
appears  that  the  color  and  moistness  of  the  soil  and  the  angle  of 
incidence  of  the  sun's  rays  are  the  most  influential ;  they  may  occa- 
sion differences  in  the  temperature  acquired  of  from  14°  to  15°  C, 
(25°  to  27°  F.)  The  nature  of  the  surface  and  the  composition  of 
the  soil  are  far  from  producing  such  marked  difTerences  ;  although, 
according  to  M.  Schiibler,  the  effect  of  inclination  is  very  decided, 
dnd  may  occasion  a  difference  to  the  amount  of  25°  C,  (45°  F.) 


CLASSIFICATION    OF   SOILS. 

Agriculturists  class  soils  according  to  their  fertility,  and  the 
cropping  which  they  will  stand  to  advantage.  In  practice  two  grand 
divisions  have  been  adopted  :  strong  soils,  and  light  soils  ;  every 
soil  belongs  wholly  or  in  part  to  one  or  other  of  these  divisions. 

In  strong  soils  clay  is  tue  predominating  element ;  in  light  soils  it 
is  sand  which  prevails.  The  first  are  stiff,  little  permeable,  and 
slow  in  drying ;  the  second  are  loose,  dry  speedily  and  readily,  are 
permeable,  and  less  difficult  to  labor.  Humus  always  adds  to  the 
qualities  of  these  two  kinds  of  soil,  though  possessed  of  properties 
eo  opposite  ;  but  its  utility  is  especially  remarkable  in  argillac^nif 
w  clayey  soils,  the  extreme  stiffness  of  which  it  diminishes. 


224  SOILS. 

Stiff  or  strong  soils  share  in  the  advantages  and  disadvantage* 
peculiar  to  clay ;  they  absorb  a  great  deal  of  moisture,  and  they  do 
not  dry  readily,  retaining  obstinately  a  considerable  quantity  of  wa- 
ter. The  humus  which  they  contain,  and  the  manures  which  are 
spread  upon  them  in  the  course  of  cultivation,  remain  with  them  for 
a  long  time,  preserved  as  it  were  from  the  too  active  agency  of  at- 
mospheric influences  ;  the  fertilizing  power  of  these  substances  is 
further  rarely  interfered  with  by  too  great  a  degree  >f  dryness  in  the 
soil.  Nevertheless,  in  very  wet  seasons,  and  in  years  of  extraordi- 
nary drought,  the  advantages  which  I  have  enumerated  disappear. 
In  wet  seasons  clay  lands  become  immoderately  humid,  sometimes 
they  approach  the  state  of  mere  puddle  ;  and  on  the  contrary,  under 
severe  and  long-continued  drought,  they  become  so  hard  that  the 
roots  of  vegetables  can  no  longer  penetrate  them,  and  then  they 
crack  in  all  directions,  and  the  roots  perish  for  want  of  being  prop- 
erly covered.  I  might  add  that  severe  frost  is  the  cause  of  effects 
disadvantageous  in  the  same  degree;  so  that  very  stiff  Ciays  are 
liable  to  the  same  bad  effects  under  the  influsnce  of  two  causes  dia- 
metrically opposed  :  the  great  heat  of  summer  and  the  severe  cold 
of  winter. 

In  such  soils  all  agricultural  operations  are  often  impracticable  ; 
changed  into  a  liquid  mud,  neither  horse  nor  plough  can  be  put  i;pon 
them,  or  baked  into  a  mass  having  the  hardness  of  stone,  the  share 
will  not  penetrate  them. 

Light  soils  rarely  accumulate  an  excess  of  moisture  in  their  inter- 
stices, so  that  they  are  liable  to  suffer  under  want  of  rain  of  even 
short  continuance.  They  are  worked  with  infinitely  greater  ease, 
and  at  much  less  expense  ;  vegetation  upon  them  is  quicker,  and 
harvests  earlier ;  but  manure  is  less  profitable  than  in  clayey  soils, 
because  the  rains  dissolve  and  carry  it  away. 

The  defects  of  these  two  kinds  of  soils  are  precisely  of  a  nature 
to  compensate  one  another,  and  it  is  in  fact  by  a  mixture,  or  that 
which  is  equivalent  to  a  mixture  of  these  two  extreme  kinds  of  soil, 
that  those  lands  are  formed  which  are  admitted  to  be  the  best  adapted 
to  cultivation,  and  the  most  fertile  of  all.  Messrs.  Thaer  and  Einhoff, 
in  submitting  to  mechanical  analysis  an  immense  number  of  arable 
soils,  and  in  studying  at  the  same  time  the  system  of  culture  best 
adapted  to  these  soils,  and  to  their  relative  fertilities,  have  given  us 
results  of  great  importance,  and  which  may  be  made  the  basis  of  a 
practical  classification  of  arable  soils.* 

An  argillaceous  or  clayey  soil  properly  so  called,  generally  con- 
tains about  40  per  cent,  of  sand.  If  the  quantity  of  sand  be  less 
than  this,  the  crop  from  such  a  soil  will  be  more  or  less  precarious, 
and  the  tenacity  will  be  sv  ch,  that  tonsiderable  difficulty  will  be  ex- 
perienced and  necessary  expense  incurred  in  working  it ;  such  a 
clayey  soil,  (having  at  least  40  per  cent,  of  sand,)  when  it  contains 
a  sufficient  quantity  of  humus  and  is  properly  treated,  may  be  regard- 
ed as  favorable  for  wheat.     Barley  succeeds  better  than  wheat,  when 

*  Thaer's  Rational  Principles  of  Agricaltiue,  <in  French,)  vol.  ii.  p.  11& 


CLASSIFICATION.  225 

the  quantity  of  sand  is  as  low  as  30  per  cent.  With  less  than  30 
per  cent,  oats  will  thrive.  Wheat  may  still  be  advantageously  cul 
tivated  upon  lands  that  contain  from  40  to  50  per  cent,  of  sand  ; 
beyond  this  term,  when  the  soil  contains  from  50  to  60  per  cent,  of 
sand,  it  is  more  advantageous  to  grow  barley.  Such  a  soil  will  not 
be  completely  pulverized  by  reiterated  ploughing,  as  will  that  which 
contains  a  larger  proportion  of  silicious  matter,  and  it  does  not  be- 
come hard  and  cracked  under  drought  like  lands  that  are  more 
essentially  clayey,  because  it  retains  a  sufficiency  of  moisture  ;  it  is 
equally  well  adapted  for  trefoil  of  all  kinds,  for  tubers,  for  plants 
with  tap  roots,  and  for  many  other  crops  of  great  marketable  value, 
such  as  cabbage,  flax,  tobacco,  &c.  It  is  almost  always  accessible, 
a  circumstance  which  allows  of  the  greatest  care  being  bestowed 
upon  the  crops  which  are  raised  upon  it.  In  soils  which  yield  on 
washing  from  60  to  80  per  cent,  of  sand,  we  cannot  reckon  securely 
on  the  success  of  wheat.  At  70  of  sand,  it  ceases  to  be  well  adapted 
to  the  cultivation  oi  this  grain,  except  with  especial  precautions  ;  but 
it  is  still  well  adapted  to  barley,  and  it  is  in  such  a  soil  especially 
that  rye  succeeds  best. 

Land  with  such  a  dose  of  sand  is  always  easily  labored,  but  it  is 
more  apt  to  be  overrun  by  foul  weeds  than  a  soil  that  is  decidedly 
argillaceous.  Manures  are  speedily  consumed  in  it  for  the  reason 
already  given  ;  it  is,  therefore,  advantageous  to  manure  such  land 
frequently,  laying  on  less  dung  at  a  time.  A  soil  having  75  per  cent, 
of  sand,  is  qualified  by  Thaer  as  an  oat  soil,  and  even  up  to  85  per 
cent,  of  sand  it  may  be  regarded  as  suitable  to  this  grain  ;  this  term 
passed,  nothing  but  rye  or  buckwheat  ought  to  be  sown  upon  it, 
and  that  only  after  it  has  had  a  sufficient  dose  of  manure.  The  re- 
iterated ploughings  which  some  of  these  sandy  soils  require  to  get 
rid  of  the  foul  v  eeds  which  rush  up  in  such  quantities  upon  them, 
sometimes  rendt  them  so  open  that  rye  will  not  succeed.  The  best 
course  is  then  to  'ay  them  down  in  grass,  and  allow  them  to  become 
consolidated  by     -st. 

It  is  extremely  diff.cult,  at  least  in  this  climate  of  ours,  to  make 
any  thing  of  soils  that  contain  90  per  cent,  of  sand ;  in  times  of 
drought  they  become  true  moving  sands.  As  we  have  already  shown, 
calcareous  matter  may  replace  silicious  sand  in  the  part  which  it 
plays  in  an  arable  soil ;  like  sand,  calcareous  matter  tends  to  de- 
stroy the  strong  cohesion  of  the  particles  of  clay  :  but  it  appears  that 
chalk  or  lime,  especially  when  it  is  in  a  state  of  minute  subdivision, 
besides  this  effect,  really  contributes  to  the  amelioration  of  wheat 
lands. 

The  feiUowing  table  comprises  the  results  obtained  by  Thaer  and 
Einhoif.  I  must  observe,  however,  and  from  causes  which  have 
been  already  explained  as  influencing  the  determination  of  the  humus, 
that  this  substance  is  evidently  estimated  at  much  too  high  a  figure 
in  several  of  these  analyses,  which  deserve  to  be  made  anew  under 
the  precautions  that  are  now  familiarly  known. 


226 


SOIL. 


Soils  according  to  com- 
position. 


Clay  with  humus 

ditto 

ditto 

Marly  soil 

Light  soil,  with  humus. 

Sandy  soil,  humus 

Argillaceous  land 

Marly  soil 

Ai^illaceous land.  .... 
suffer  argillaceous  land 

Clay 

Stiff  argillaceous  land. . 

ditto 

Sandy  clay 

ditto 

Clayey  sand 

ditto 

Sandy  soil 

ditto 

ditto 


Usually  designated. 


Rich  wheat  land 

ditto 

ditto  

ditto 

Meadow  land 

Rich  barley  land    

Good  wheat  land 

Wheatland 

ditto 

ditto 

ditto 

Barley  land  of  the  1st  class  | 
ditto  2d  class 

ditto  ditto 

Oat  land 

ditto 

Rye  land 

ditto  

ditto 

ditto  


i 

ji 

1 

aS 

rs 

5 

i 

3 

s 

74 

10 

4 

11.5 

81 

6 

4 

8.5 

79 

10 

4 

6.5 

40 

22 

36 

4 

14 

49 

10 

27 

20 

67 

3 

10 

58 

36 

2 

4 

56 

30 

12 

2 

60 

38 

2 

48 

50 

2 

68 

30 

2 

38 

60 

2 

33 

()5 

2 

28 

70 

2 

23.5 

75 

1.5 

18.5 

80 

1.5 

14 

85 

1 

9 

90 

1 

4 

95 

0.75 

2 

97.5 

0.5 

Schwertz  has  given  a  summary  of  the  opinions  of  Thaer  upon  the 
value  of  different  soils  from  an  eminently  practical  point  of  view. 
Agreeing  with  this  distinguished  agriculturist,  that  it  is  well  to  judge 
of  the  soil  by  its  produce,  he  also  forms  a  scale  of  comparison  after 
the  different  kinds  of  grain,  taking  as  extreme  terms  wheat  and  bar- 
ley, the  first  succeeding  in  bad  argillaceous  soils,  the  second  still 
growing  in  sandy  soils  of  the  poorest  description.  In  these  extreme 
or  boundary  soils,  wheat  and  barley  succeed  very  indifferently  in- 
deed ;  but  between  the  two  extremes  are  comprised  every  variety  of 
soil  which  results  from  the  fusion  of  the  strongest  or  stifTest  with  the 
lightest  soils,  from  the  most  tenacious  clay  up  to  loose  sand.  In 
these  mixed  soils  of  intermediate  qualities,  v;heat  and  barley  gradu- 
ally approach  one  another,  taking  the  place  successively  of  barley, 
oats,  and  buckwheat,  until  they  meet  in  the  middle  of  the  scale  in 
a  kind  of  neutral  soil,  upon  which  every  variety  of  grain  may  be 
grown. 

Schwertz  arranged  his  scale  in  the  following  manner  :* 

0.  Moving  sand 0.  Stiff  clay, 

1.  Rye  land 1.  Wheat  land. 

2.  Rye  and  buckwheat  land 2.  Wheat  and  oat  land. 

3.  Rye,  buckwheat,  and  oat  land 3.  Wheat,  oat,  and  barley  land. 

4.  Rye,  oat,  and  small  barley  land 4   Wheat  and  large  barley  land. 

5.  Wheat,  rye,  barley,  »;<  oat  land. 

The  species  of  soil  which  suit  these  different  crops  are : 

1.  Light  dry  sand 1.  Cold  stiff  clay.  -, 

8.  Moist,  very  slightly  argillaceous  sand-  •  .2.  A  lighter  moist  clay.  *' 

3.  Argillaceous  sand 3.  A  warm  dry  clay  < 

4,  Sandy  clay 4.  Rich  clay. 

5.  Clay. 

•  precepts  of  Practical  Agricuituro,  (in  French,)  p.  40. 


CLASSIFICATION.  227 

The  preceding  considerations  are  more  than  sufficient  to  give  a 
precise  idea  of  what  is  to  be  understood  in  regard  to  the  composition 
of  arable  soils.  Nevertheless,  with  a  view  to  making  the  subject 
more  complete,  I  shall  quote  a  few  of  the  analyses  of  arable  soils, 
published  by  different  chemists  at  a  time  when  a  certain  importance 
was  attached  to  researches  of  this  kind.  I  may  remark  generally, 
that  from  the  whole  of  the  analyses  of  good  wheat  lands  which  have 
hitherto  been  made,  it  appears  that  carbonate  of  lime  enters  in  con- 
siderable quantity  into  their  composition  ;  and  theory,  in  harmony 
with  practice,  tends  to  show  that  it  is  advantageous  to  have  this 
earthy  salt  as  a  constituent  in  the  manures  which  are  put  upon  soils 
that  contain  little  or  no  lime. 

Analysis  of  a  soil  under  the  variety  of  rape  called  colza,  by  M. 
Berthier : 

Silica 78.2 

Alumina 7.1 

Peroxide  of  iron 4.4 

Lime 1.9 

Magnesia 0.8 

Carbonic  acid t  1.4 

Water 5.8 


This  soil  was  dried  in  the  air,  after  having  been  reduced  to  pov/- 
der ;  it  lost  34  per  cent,  by  drying.  It  is  remarkable  that  it  con- 
tains no  trace  of  organic  matter,  the  rather  as  it  was  held  favorable 
for  colewort.  M.  Berthier  believes  that  this  soil  would  gain  in  fer- 
tility by  the  addition  of  a  certain  quantity  of  calcareous  matter,  and 
M.  Cordier*  explains  its  inability  to  grow  grain  to  advantage  from 
the  deficiency  in  lime.  The  stalk  of  the  grain  gniwn  in  this  soil  is 
weak,  especially  in  wet  seasons,  and  the  seed  is  particularly  apt  to 
shake  out  when  it  is  ripe. 

If  the  presence  of  lime  in  a  wheat  soil  is  a  guaranty  against  loss 
by  shaking  in  harvest,  M.  Berthier's  analysis  is  still  far  from  proving 
that  the  presence  of  lime  in  a  soil  is  indispensable,  inasmuch  as 
beautiful  wheat  crops  are  grown  in  the  neighborhood  of  Lisle  without 
lime.  In  proof  of  this  fact,  I  shall  here  cite  the  analysis  of  one  of 
the  most  fertile  soils  in  the  world,  the  black  soil  of  Tchornoizem, 
which  Mr.  Murohison  informs  us  constitutes  the  superficies  of  the 
arable  lands  comprised  betvt^een  the  54th  and  57th  degrees  of  north 
latitude,  along  the  left  bank  of  the  Volga  as  far  as  Tcheboksar,  from 
Nijni  to  Kasan,  and  stretching  over  a  still  more  extensive  district 
upon  the  Asiatic  side  of  the  Ural  mountains.  Mr.  Murchison  is  of 
opinion  that  this  land  is  a  submarine  deposite  formed  by  the  accumu- 
lation of  sands  rich  in  organic  matters.  The  Tchornoizem  is  com- 
posed of  black  particles  mixed  with  grains  of  sand ;  it  is  the  best 
soil  in  Russia  for  wheat  and  pasturage  ;  a  year  or  two  of  fallow  will 
suffice  to  restore  it  to  its  former  fertility  after  it  has  been  exhausted 
by  cropping  ;  it  is  never  manured. 

M.  Payen  found  in  this  black  and  fertile  soil : 

♦  On  the  Agriculture  of  French  Flanders,  p.  SCKJ,  <in  French.) 


838  SOIL. 

Silica 71.56 

i\luniina •  11.40 

Oxide  of  iron 5.62 

Lime 0.80 

Magnesia 1.22 

Alkaline  chlorides 1.21 

Phosphoric  acid a  trace. 

Loss 1.24 

100.00 

Bergman  gives  the  following  as  the  composition  of  a  fertDe  soil  v 

Sweden : 

Carbonate  of  lime 30 

Gravel 30i 

Silicious  sand 26  v  Clay 

Alumina 14j 

100.0 

Several  fertile  soils  of  Senegal,  examined  by  M.  Laugier,  con- 
ained  : 

K.awei. 

Silicious  sand  and  silica 87.0 

Alumina 3.6 

Oxide  of  iron 3.4 

Carbonate  of  lime trace 

Orga  ni  c  matter  and  water 4.4 

Loss 1.6         

100.0       100.0       100.0      100.0       I00.0 

M.  Plagne,  who  has  studied  the  agriculture  of  the  Coromandel 
coast,  divides  the  soils  he  met  with  there  into  argillaceous,  or  clayey, 
sandy,  and  mixed,  and  gives  their  several  compositions  as  follows  : 

Ar^illaceoui.  Sandy.  Mixed. 

Silica 22.0  82.0  64.0 

Alumina 59.0  6.5  19.5 

Carbonate  of  lime 3.5  3.5  2.5 

Oxide  of  iron 2.5  4.0  iA 

Phosphate  of  magnesia "  )  an  t«oo 

Sulphate  of  lime "S  ^^ 

Azotized  organic  matter 5.0  "  7.0 

Water  and  loss 8.0  2.0  3.0 

100.0  100.0  100.0 

The  soils  in  which  the  tea-plant  is  grown  in  Assam  and  China, 
have  been  examined  by  Mr.  Piddington  ;*  they  contain  respectively  : 

Chinese  soil.  Assam  soil. 

Silica  and  sand 76.0  84.8 

Alumina 9,0  4.5 

Oxideoflron 9.9  7.0 

Phosphate  and  sulphate  of  lime 1 .0  traces 

Organic  matter 1.0  1.5 

Water • 3^  2.3 

99.9  100.1 

Sir  Humphrey  Davy  found  the  various  soils  most  generally  culti- 
fated  in  England,  to  have  the  following  composition  : 

•  Roi>iaiKMi,  .\ccouat  of  A.vsam,  p.  130. 


LOCALITIES. 

oukitt. 

Diajue. 

Roso. 

N'Dick. 

72.0 

89.0 

78.0 

91.0 

10.0 

3.0 

7.0 

1.8 

8.0 

3.6 

5.2 

3.0 

trace 

0.5 

trace 

0.5 

10.0 

3.6 

9.0 

3.0 

OJ 

0.8 

0.7 

CLASSIFICATION. 


229 


Districts. 

1^ 

2 

i 
1 

i 

— 

1 

"3   . 

£ 

i 
<3 

if 

} 

i 
1 

J 

Remark*. 

County  of  Kent 

Norfolk 

Middlesex 

Worcestershire 
Vale  of  the  Teviot 
Salisbury 

66.3 

88.9 

60.0 

60.0 
83.3 
91 

5.2 

1.7 

12.8 

16.4 
7.0 
12.7 

3.3 

1.2 

11.6 

14.0 
6.8 
6.4 

4.8 

7.0 

11.2 

5.6 

0.7 

57.3 

0.8 

1.. 

0.3 

1.2 
0.8 

1.8 

8.0 

0.6 

4.4 

2.8 

1.4 

12.7 

05 

4.9 
0.3 

.0 

{  Rich  soil, 
}  under  hops, 
j  Ditto  under 
(     turnips. 
\  Ver^-  good 
\  soil,  vvheat. 
\  Very  lertUe 
}      soil. 

Good  soil. 
\  Excellent 
}  grazing  soil 

M.  Gasparin  has  published  analyses  of  the  soils  of  the  south  of 
France.  Instead  of  destroying  the  humus  and  organic  matter  by- 
calcination,  as  Davy  and  the  generality  of  analysts  did,  M.  Gasparin 
dissolved  out  the  humus  by  means  of  a  strong  alkaline  solution. 
This  method  of  procedure  is.  however,  at  least  as  liable  to  objection 
as  the  other. 


Districts 

Humus. 

Calca- 
reous 
matter. 

Clay. 

Sand. 

Remarks. 

From  Thor  (Vaucluse) 

Alluvium  of  the  Rhone 

From  Palus,  near  Orange 

Old  deposite  of  the  Rhone 

From  the  plains  near  Orange 
Neighborhood  of  Auch 

7.5 

3.4 

2.5 

5.0 

4.0 
1.5 

92.5 

2.3 

555 

32.5 

50.0 
3.5 

6.0 

53.5 

43.5 

56.0 

48.0 
73.0 

1.5 

42.7 

1.0 

11.5 

2.0 
23.0 

Middling  wheat  soil. 
<  Well  adapted  for  mad- 
(    der,  wheat  &  lucern. 

Bad  wheat  land.  ->.^ 
i  Good  wheat  land,  vgy^ 
(  indifferent  for  madder. 

Ditto,  bad  for  njadder. 

There  is  an  important  element  which  must  always  be  taken  into 
the  account  in  estimating  the  value  of  soils,  no  matter  what  their 
special  composition  ;  this  element  is  their  depth,  or  thickness.  In 
running  a  deepish  furrow  in  a  cultivated  field,  we  generally  distin- 
guish at  a  glance  the  depth  of  the  superficial  layer,  which  is  com- 
monly designated  as  the  mould  or  vegetable  earth  ;  this  is  a  layer 
generally  impregnated  with  humus,  and  looser  and  more  friable  than 
the  subsoil  upon  which  it  rests.  The  thickness  of  this  superficial 
layer  is  extremely  variable  ;  it  is  frequently  no  more  than  about  3 
inches ;  but  it  is  also  encountered  of  every  depth  from  3  or  4  lo  12 
or  13  inches.  It  must  be  held  an  exceptional  and  unusual  case  when 
it  has  a  depth  of  3  feet  or  more.  Nevertheless  we  do  meet  with 
collections  of  vegetable  soil  of  great  depth,  deposited  by  rivers, 
washed  down  into  the  bottoms  of  valleys,  or  accumulated  on  the 
surface,  as  in  the  virgin  forests  or  vast  prairies  of  America.  Depth 
of  mould,  or  vegetable  soil,  is  always  advantageous  ;  it  is  one  of  th» 

20 


230  DEPTH  OP  SOIL. 

best  conditions  to  successful  agriculture.  If  we  nave  depth  of  soil, 
and  the  routs  of  our  plants  do  not  penetrate  sufficiently  to  derive 
benefit  froui  the  fertility  that  lies  below,  we  can  always,  by  working 
a  little  deeper,  bring  up  the  inferior  layers  to  the  surface,  and  so 
make  them  concur  in  fertilizing  the  soil.  And,  independently  of 
this  great  advantage,  a  deep  soil  suffers  less  either  from  excess  or 
deficiency  of  moisture  ;  the  rain  that  falls  has  more  to  moisten,  and 
is  therefore  absorbed  in  greater  quantity  than  by  thin  soils,,  and, 
once  imbibed,  it  remains  in  store  against  drought. 

The  layer  upon  which  the  vegetable  earth  rests,  is  the  subsoil, 
which  it  is  of  importance  to  examine,  inasmuch  as  the  qualities,  and, 
consequently,  the  value  of  an  arable  soil,  have  always  a  certain  rela- 
tion with  the  nature  and  properties  of  this  subjacent  stratum.  Fre- 
quently, and  especially  in  hilly  countries,  the  mineral  constitution  of 
the  subsoil  is  the  same  as  that  of  the  soil,  and  any  difference  that 
the  former  may  present  is  owing  especially  to  the  presence  of  humus, 
and  to  the  looser  condition  which  results  from  the  growth  of  vege- 
tables, from  ploughing,  &c.,  and  not  from  atmospheric  influences. 
By  deep  ploughing  done  cautiously,  the  thickness  of  the  layer  of 
arable  land  may  be  increased  at  the  expense  of  the  subsoil,  and, 
when  plenty  of  manure  can  be  commanded,  the  operation  will  go  on 
with  considerable  rapidity.  Still  it  is  maintained,  and  indeed  in 
many  cases  it  is  unquestionable,  that  the  soil  loses  temporarily  some 
portion  of  its  fertility  by  the  introduction  of  a  certain  quantity  of  the 
subsoil,  and  that,  under  ordinary  circumstances,  several  years  elaps» 
before  any  amelioration  becomes  perceptible. 

In  plains,  in  high  table-lands,  the  analogy,  in  point  of  constitution, 
between  the  soil  and  subsoil  is  not  so  constant.  In  such  situations 
the  arable  land  is  frequently  an  alluvial  deposite  proceeding  from  the 
d_es*ruction  or  disintegration  of  rocks  situated  at  a  great  distance. 
When  the  superior  strata  possess  properties  that  are  entirely  differ- 
ent from  the  subsoils,  it  may  be  understood  how  the  vegetable  earth 
may  be  improved  by  the  addition  of  a  certain  dose  of  the  subsoil,  and 
this  is  the  case  in  which  the  amelioration  is  the  least  expensive. 
The  impermeability  of  the  subsoil  is  one  grand  cause  of  the  too  great 
humidity  of  a  cultivated  soil.  A  strong  soil,  very  tenacious  through 
the  excess  of  clay  which  it  contains,  has  its  disadvantageous  proper- 
ties considerably  lessened,  if  the  subsoil  upon  which  it  rests  is  sandy, 
1st,  from  the  evident  amelioration  which  must  result  from  an  ad- 
mixture of  the  two  layers,  and,  next,  because  it  is  always  a  positive 
advantage  in  having  a  soil  which  has  a  strong  affinity  for  water 
superposed  upon  a  subsoil  which  is  extremely  permeable.  The  in- 
verse situation  is  scarcely  less  desirable ;  a  light  friable  soil  will  have 
greater  value  if  it  lies  upon  a  bottom  of  a  certain  consistency,  and 
capable  of  retaining  moisture  ;  wil  i  this  condition,  however,  that  the 
clayey  layer  shall  not  be  too  uneven  in  its  surface,  that  it  shall  not 
present  great  hollows  in  which  water  may  collect  and  stagnate  ;  an 
impermeable  subsoil,  to  act  beneficially  in  such  circumstances,  must 
have  a  suflScient  inclination  to  admit  of  its  draining  itself.  The  most 
essential  distinction,  then,  in  regard  to  the  nature  of  subsoils  is,  int» 


SOILS    IN    REFERENCE   TO    CLIMATE.  231  . 

permeable  and  impermeable.  Acquainted  with  the  nature  of  vege- 
table earth,  it  is  easy  to  judge  of  the  advantages  or  disadvantages 
which  will  be  presented  by  subsoil  having  the  faculty  of  retaining  or 
of  permitting  the  escape  of  moisture. 

In  some  situations,  particularly  upon  the  slopes  of  hills,  the  layer 
of  arable  land  is  of  very  limited  thickness,  and  it  is  not  uncommon 
to  see  it  lying  upon  rocks  of  the  most  dense  description,  such  as 
granite,  porphyry,  basalt,  &c.  ;  in  such  circumstances  the  substrata 
are  unavailable,  and  there  is  nothing  for  it  then  in  the  way  of  ame- 
lioration except  to  transport  directly  vegetable  earth  from  other 
situations.  Mica  schist  is  perhaps  the  least  intractable  rocky  sub- 
soil ;  the  plough  often  penetrates  it,  and  in  the  long  run  it  becomes 
mingled  with  the  arable  layer.  It  is  generally  agreed  that  limestone 
rocks  form  a  less  unfavorable  substrate.  There  are  in  fact  some 
calcareous  rocks  which  absorb  water,  and  crumble  away,  and  the 
roots  of  various  plants,  such  as  cinquefoin,  penetrate  them  deeply  ; 
but  there  are  many  limestone  rocks  so  hard  that  they  resist  all  de- 
composing action  for  a  very  long  period  of  time. 

The  qualities  which  we  have  thus  far  sought  to  determine  in  soils, 
do  not  depend  solely  on  their  mineral  constitution  or  their  physical 
properties,  nor  yet  on  those  of  the  subsoils  which  support  them. 
These  qualities  to  become  obvious  require  that  the  soils  shall  be 
placed  in  certain  conditions  which  must  not  be  left  out  of  the  reck- 
oning. Such  are  those  of  the  climate  enjoyed  and  of  the  position 
more  or  less  inclined  to  the  horizon  in  one  direction  or  another. 
The  precepts  which  we  have  laid  down  are  especially  applicable  to 
the  arable  lands  of  Germany,  England,  and  France.  But  in  gener- 
alizing it  would  be  proper  to  say  that  clayey  lands  answer  better  in 
dry  climates,  and  light  sandy  soils  in  countries  where  rains  are  fre- 
quent. Kirwan  made  this  remark  long  ago  in  connection  with  nu- 
merous analyses  of  wheat  lands.  The  conclusion  to  which  this 
celebrated  chemist  came  was  this,  that  the  soil  best  adapted  for  wheat 
in  a  rainy  country  must  be  viewed  in  a  very  different  way  with  refer 
ence  to  a  country  where  the  rains  are  less  frequent.  The  fertility 
of  light  sandy  soils  is  notoriously  in  intimate  relationship  with  the 
frequent  fall  of  rain.  At  Turin,  for  example,  where  a  great  deal  of 
rain  falls,  a  soil  which  contains  from  77  to  80  per  cent,  of  sand  is 
still  held  fertile,  while  in  the  neighborhood  of  Paris,  where  it  rains 
less  frequently  than  at  Turin,  no  good  soil  contains  more  than  50  pei 
cent,  of  sand.  A  light  sandy  soil  which  in  the  south  of  France 
would  only  be  of  very  inferior  value,  presents  real  advantages  in  the 
moist  climate  of  England.*  Irrigation  supplies  the  place  of  rain, 
and  in  those  countries  or  situations  where  recourse  can  be  had  to  it, 
the  question  in  regard  to  the  constitution  of  soils  loses  nearly  the 
whole  of  its  interest.  Land  that  can  be  irrigated  has  only  to  be 
loose  and  peimeable  in  order  to  have  the  whole  of  the  fertility  de- 
veloped which  climate  and  manure  can  confer.  Sandy  deserts  are 
sterile  because  it  never  rains.     Upon  the  sandy  downs  of  the  coasts 

♦  Sinclair's  Practical  Agricultnre. 


232  SOILS    If    REFERENCE    TO   CLIMATE. 

of  the  Southern  Ocean,  a  brilliant  vegetation  is  seen  along  the  course 
of  the  few  rivers  which  traverse  them  ;  all  beyond  is  dust  and  sler* 
ility.  I  have  seen  rich  crops  of  maize  gathered  upon  the  plateau  of 
the  Andes  of  Quito  in  a  sand  that  was  nearly  moving,  but  which 
was  abundantly  and  dexterously  irrigated. 

A  sandy  and  little  coherent  soil  is  by  sc  much  the  more  favorably 
situated  as  it  lies  in  the  least  elevated  parts  of  a  district ;  it  is  then 
less  exposed  to  the  effects  of  drought ;  any  considerable  degree  of 
inclination  is  unfavorable  to  such  a  soil,  inasmuch  as  the  rain  drains 
off  too  quickly,  and  because  it  is  itself  apt  to  be  washed  away.  It 
is  to  prevent  this  action  of  the  rains,  that  the  abrupt  slopes  of  hills 
are  generally  left  covered  with  trees  ;  and  the  deplorable  conse- 
quences which  have  followed  from  cutting  down  the  woods  in  moun- 
tainous countries  are  familiarly  known. 

Strong  soils,  on  the  contrary,  are  better  placed  in  opposite  cir- 
cumstances. A  certain  inclination  is  peculiarly  advantageous  to 
them  ;  and,  indeed,  in  working  clayey  lands  that  stand  upon  a  dead 
level,  we  are  careful  to  ridge  them  in  such  a  way  as  to  favor  the 
escape  of  water. 

In  countries  situated  beyond  the  tropics,  where  consequently 
shadows  are  cast  in  the  same  direction  throughout  the  whole  year, 
the  exposure  of  a  piece  of  land  is  by  no  means  matter  of  indiffer- 
ence. In  our  hemisphere,  the  lands  which  have  a  considerable  in- 
clination and  a  northern  exposure,  receive  less  heat  and  light,  and 
remain  longer  wet  than  those  that  slope  towards  the  south  ;  vegeta- 
tion consequently  is  less  forward  upon  the  former  than  the  latter 
lands  :  but,  on  the  contrary,  the  latter  are  less  exposed  to  suffer 
from  want  of  rain  ;  and  it  is  a  fact,  now  well  ascertained  from  data 
collected  in  Switzerland  and  in  Scotland,  that  the  slopes  which  de- 
scend towards  the  north,  if  they  be  only  not  too  abrupt,  are  actually 
the  most  productive.  This  kind  of  anomaly  is  explained  by  the  fre- 
quence and  rapidity  of  the  thaws  which  take  place  upon  slopes  that 
lie  to  the  south.  Frost,  when  not  too  intense,  is  certainly  less  inju- 
rious to  vegetables  than  too  rapid  a  thaw  ;  and  it  is  easy  to  under- 
stand that  in  situations  where,  from  the  mere  effect  of  nocturnal 
radiation,  vegetables  are  covered  almost  every  morning  through  the 
spring  with  hoar  frost,  a  rapid  thaw  must  take  place  every  day  im- 
mediately after  the  rise  of  the  sun.  With  a  northern  exposure,  the 
frost  occurs  in  the  same  measure  ;  but  the  cause  of  its  cessation 
does  not  operate  so  suddenly,  the  fusion  of  the  rime  being  effected 
by  the  gradual  rise  in  temperature  of  the  surrounding  air.  In  other 
respects,  it  is  obvious  that  the  advantages  and  disadvantages  of  dif- 
ferent exposures  are  connected  with  the  nature  and  the  constitution 
of  soils.  The  same  may  be  said  with  reference  to  means  of  shelter 
from  the  action  of  prevailing  winds.  Stiff  wet  lands  are  much  bene- 
fited by  the  action  of  free  currents  of  air ;  our  stiff  soils  at  Bechel- 
bronn  remain  impracticable  for  our  ploughs  during  but  too  long  a 
period  of  the  spring,  when  they  have  not  been  well  dried  in  the 
months  of  March  and  April  by  strong  winds  from  the  east.  Light 
and  sandy  soils,  again,  require  to  be  well  sheltered.     The  whole  ob- 


IMPROVEMENT    OF    SOILS.  2SS 

ject  of  Studying  the  soil,  is  its  amelioration ;  the  industry  of  the 
agriculturist  is,  in  fact,  more  effectually  bestowed,  and  exerts  a 
greater  amount  of  influence  upon  the  soil  than  upon  all  the  other  and 
varied  agents  which  favor  vegetation. 

To  improve  a  soil  is  as  much  as  to  say  that  we  seek  to  modify  its 
constitution,  its  physical  properties,  in  order  to  bring  them  into  har- 
mony with  the  climate  and  the  nature  of  the  crops  that  are  grown. 
In  a  district  where  the  soil  is  too  clayey  our  endeavor  ought  to  be,  to 
make  it  acquire  to  a  certain  extent  the  qualities  of  light  soils. 
Theory  indicates  the  means  to  be  followed  to  effect  such  a  change  ; 
it  suffices  to  introduce  sand  into  soils  that  are  too  stiff,  and  to  mix 
clay  with  those  that  are  too  sandy.  But  these  recommendations  of 
science  which,  indeed,  the  common  sense  of  mankind  had  already 
pointed  out,  are  seldom  realized  in  practice,  and  only  appear  feasible 
to  those  who  are  entirely  unacquainted  with  rural  economy.  The 
digging  up  and  transport  of  the  various  kinds  of  soil  according  to 
the  necessities  of  the  case,  are  very  costly  operations,  and  I  can 
quote  a  particular  instance  in  illustration  of  the  fact :  my  land  at 
Bechelbronn  is  generally  strong ;  experiments  made  in  the  garden 
on  a  small  scale  showed  that  an  addition  of  sand  improved  it  consid- 
erably. In  the  middle  of  the  farm  there  is  a  manufactory  which 
accumulates  such  a  quantity  of  sand  that  it  becomes  troublesome  ; 
nevertheless,  I  am  satisfied  that  the  improvement  by  means  of  sand 
would  be  too  costly,  and  that  all  things  taken  into  account,  it  would 
be  better  policy  to  buy  new  lands  with  the  capital  which  would  be 
required  to  improve  those  I  already  possess  in  the  manner  which  has 
been  indicated,  I  should  have  no  difficulty  in  citing  numerous  in- 
stances where  improvements  by  mingling  different  kinds  of  soil  were 
ruinous  in  the  end  to  those  who  undertook  them. 

A  piece  of  sandy  soil,  for  example,  purchased  at  a  very  low  price, 
after  having  been  suitably  improved  by  means  of  clay,  cost  its  pro- 
prietor  much  more  than  the  price  of  the  best  land  in  the  country. 
Great  caution  is  therefore  necessary  in  undertaking  any  improvement 
of  the  soil  in  this  direction, — in  changing  suddenly  the  nature  of  the 
soil.  Improvement  ought  to  take  place  gradually  and  by  good  hus- 
bandry, the  necessary  tendency  of  which  is  to  improve  the  soil. 
Upon  stiff  clayey  lands  we  put  dressings  and  manures  which  tend 
to  divide  it,  to  lessen  its  cohesion,  such  as  ashes,  turf,  long  manure, 
&c.  But  the  husbandman  has  not  always  suitable  materials  at  his 
command,  and  in  this  case,  which  is  perhaps  the  usual  one,  he  must 
endeavor,  by  selecting  his  crops  judiciously,  crops  which  shall  agree 
best  with  stiff  soils,  and  at  the  same  time  meet  the  demands  of  his 
market,  to  make  the  most  of  his  land.  In  a  word,  the  true  husband- 
man ought  to  know  the  qualities  and  defects  of  the  land  which  he 
cultivates,  and  to  be  guided  in  his  operations  by  these  ;  and  in  fact 
it  is  only  with  such  knowledge  that  he  can  know  the  rent  he  can 
afford  to  pay,  and  estimate  the  amount  of  capital  which  he  can  rea- 
sonably employ  in  carrying  on  the  operations  of  his  farm. 

In  an  argillaceous  or  clayey  soil,  which  we  have  seen  above  is  the 
best  adapted  for  wheat  in  these  countries,  it  would  be  absurd  to  per- 

20* 


894  IMPROVEMENT   OF   SOILS. 

sist  in  attempting  to  grow  crops  that  require  an  open  soil.  Clayey 
lands  generally  answer  well  for  meadows,  and  autumn  ploughing  is 
always  highly  advantageous  to  them  by  reason  of  the  disintegrating 
effects  of  the  ensuing  winter  frost. 

Chalk  occupies  a  large  space  in  recent  formations  ;  as  a  general 
rule,  the  soil  it  supports  immediately  is  of  no  great  fertility.  Sir 
John  Sinclair  proposed  to  improve  such  soil  by  growing  green  crops 
and  consuming  them  upon  the  spot.  Properly  treaicd,  the  chalky 
soils  of  England  produce  trefoil,  turnips,  and  barley,  and  they  ar« 
particularly  adapted  to  cinquefoin.  It  is  doubtful  whether  in  France, 
where  the  climate  is  not  so  moist  as  in  England,  chalky  lands  could 
be  treated  to  advantage  on  the  English  plan.  Recent  inquiries  have 
shown  that  chalk  contains  a  small  quantity  of  phosphate  bf  lime,  a 
salt,  as  we  shall  see  by  and  by,  whose  presence  is  always  desirable 
in  arable  lands. 

Turf  or  turfy  soils  yield  rich  crops  when  we  succeed  in  converting 
the  turf  into  humus.  The  grand  difficulty  in  dealing  with  turf  is  to 
dry  it  properly,  inasmuch  as  it  is  generally  found  at  the  bottom  of 
valleys  or  of  old  lakes  and  swamps.  By  a  happy  coincidence,  turfy 
deposites  frequently  alternate  with  layers  of  sand,  of  gravel,  of  clay, 
and  of  vegetable  earth,  which  have  been  accumulated  at  the  'same 
epoch.  By  a  mixture,  by  a  division  of  these  different  materials, 
preceded  in  every  case,  however,  by  proper  draining,  mere  peat  bogs 
may  be  turned  into  good  arable  soil.  Pyrilic  turf,  however,  shows 
itself  more  intractable,  it  rarely  yields  any  thing  of  importance.  To 
improve  such  a  soil  it  is  absolutely  necessary  to  have  recourse  to 
substances  of  an  alkaline  nature,  such  as  chalk  or  lime,  wood-ashes, 
&c.,  which  have  the  property  of  decomposing  the  sulphate  of  iron 
which  is  formed  by  the  efflorescence  of  the  pyrites.  Turfy  lands 
can  also  be  brought  into  an  arable  state,  with  the  help  of  paring  and 
burning.  Scotch  agriculturists,  who  are  very  familiar  with  reclaim- 
ing land  of  this  kind,  hold,  that  the  best  method  of  improving  turf  or 
bog  lands,  is  to  turn  them  into  natural  meadows.  Where  the  wet 
and  soft  state  of  the  soil  does  not  allow  cattle  to  be  driven  upon  it, 
the  crop  of  hay  should  only  be  cut  once,  the  second  crop  should  be 
left  standing.  By  proceeding  in  this  way  mere  bogs  have  been  turned 
into  productive  meadows.*  Turfy  lands  thoroughly  drained  and  im- 
proved, present  many  advantages  connected  with  their  natural  but 
not  excessive  moistness.  In  the  neighborhood  of  Haguenau,  mag- 
nificent hop-gardens  are  found  upon  bottoms  of  this  kind  ;  madder 
also  thrives  in  it  equally  well,  and  for  certain  special  crops  it  is  in  my 
opinion  one  of  the  richest  soils. 

Sandy  soils  do  perfectly  well  in  countries  which  are  not  exposed 
to  long  droughts  ;  their  cultivation  is  attended  with  little  expense, 
and  they  grow  excellent  crops  of  turnips,  potatoes,  carrots,  and 
rye  ;  but  it  is  well  to  exclude  clover,  oats,  wheat,  and  hemp,  which 
require  a  soil  of  greater  consistence.  In  southern  countries,  a  sys- 
tem of  irrigation  is  absolutely  necessary,  in  connection  with  the 

*  Sinclair,  Practical  Agriculture 


MOVING   SANDS DOWNS.  SJSfe 

cultivation  of  sandy  soils-if  they  are  not  watered,  they  remain  nearly 
barren  ;  the  only  mode  of  making  them  productive  is  to  lay  them 
out  in  plantations  of  timber. 

Those  moving  sandy  plains  of  great  extent,  which  are  found  in  the 
interior  of  many  continents,  seem  at  first  sight  stricken  with  eternal 
barrenness  Nevertheless,  the  mobility  of  the  sand  of  the  desert, 
which  permits  it  to  be  swept  hither  and  thither,  and  to  be  tossed 
about  like  a  liquid  mass,  depends  less  upon  the  total  absence  of  ar- 
gillaceous particles  than  upon  the  want  of  the  moisture  necessary  to 
agglutinate  or  to  fix  its  grains.  The  burning  steppes  of  Africa  and 
America  have  their  oases  here  and  there,  the  surface  of  which, 
moistened  by  a  spring,  is  green  with  vegetation  ;  and  whenever 
sandy  plains  are  bathed  by  a  river,  it  is  possible  to  render  them  fit  for 
cultivation.  In  Spain,  for  instance,  in  the  neighborhood  of  San  Lu- 
car  de  Baromeda,  a  powdery  soil  of  extreme  dryness  has  been  fer- 
tilized by  the  hand  of  man.  The  mammillated  downs  of  San  Lucar 
are  covered  on  the  surface  by  a  layer  of  quartzy  sand,  so  loose  that 
it  is  blown  about  by  the  wind  ;  but  by  a  happy  disposition  of  things, 
a  lower  stratum  of  these  downs  is  kept  constantly  moist  by  the  wa- 
ters of  the  Guadalquiver,  and  it  is  only  necessary  to  remove  the  su- 
perficial sand,  and  to  level  the  surface,  in  order  to  have  a  loose  soil 
which  unites  in  the  highest  degree  two  essential  conditions  of  fer- 
tility, viz  :  openness,  and  a  constant  supply  of  moisture,  which  pene- 
trates the  soil  in  virtue  of  its  permeability  ;  under  the  influence  of  a 
fine  climate  and  manure,  the  market  gardens  established  in  the  riiidst 
of  this  desert  are  remarkable  for  the  rapidity  and  the  vigor  of  their 
vegetation.  To  avoid  great  expense,  the  labor  of  removing  the  sand 
is  only  undertaken  in  places  where  the  layer  is  least  thick  ;  and  what 
is  removed  being  heaped  up  as  a  mound  around  the  soil  which  is  clear- 
ed, a  kind  of  boundary  wall  is  formed,  which  is  not  without  its  use 
in  affording  shelter,  and  which  becomes  productive  itself  by  the 
plantations  of  vines  and  fig-trees  that  are  made  upon  it  with  a  view 
mainly  to  its  consolidation.  In  the  same  way  in  Alsace,  in  the  plains 
of  Haguenau,  the  soil  which  was  a  moving  desert  of  sand,  has,  in 
the  course  of  less  than  forty  years,  become  one  of  the  most  fertile 
under  the  influence  of  incessant  cultivation  ;  in  the  same  way  also  it 
is  that  in  Holland,  mountains  of  sand,  which  had  been  accumulated 
by  the  winds,  have  been  fixed.  This  sand,  which  rests  upon  a  wet 
bottom,  draws  up  the  moisture  by  capillary  attraction,  and  so  be- 
comes fit  to  support  certain  vegetables.  These  downs,  which  may 
be  said  to  have  come  out  of  the  sea,  have  a  constant  tendency  in 
many  places  to  encroach  upon  the  cultivated  lands.  To  oppose  their 
progress,  the  Dutch  sow  them  with  the  arundo  arenaria.  the  long 
and  creeping  roots  of  which  bind  together  the  movmg  mass  and 
imprison  the  particles  of  sand  within  a  kind  of  net-work.  These 
masses  of  sand  become  fixed  in  this  way ;  but  they  remain  nearly 
or  altogether  unproductive. 

It  is  therefore  a  problem  of  the  highest  importance  in  many  in- 
stances to  fix  permanently  masses  of  sand  blown  up  from  the  sea, 
by  covering  them  with  productive  plantations.     This  problem  wat 


£38  DOWNS ^ARREST  OF  MOVING  SANDS. 

studied  and  successfully  resolved  by  M.  Bremontier,  a  French  en 
gineer,  who  by  sagacity  in  the  choice  of  means  and  persever- 
ance in  their  employment  gave  a  complete  and  practical  solution  of 
the  question  among  the  downs  of  the  Gulf  of  Gascony.* 

The  downs  formed  by  the  sand  which  is  thrown  up  by  the  ocean 
between  the  mouths  of  the  Adour  and  the  Girond,  occupy  a  surface 
of  75  square  leagues  and  have  a  mean  elevation  of  from  60  to  70 
feet,  'rhey  form  a  multitude  of  hillocks,  which  appear  co.iUected 
by  their  bases,  the  crowns  of  many  of  them  rising  to  a  height  of 
160  feet  and  upwards.  Under  the  influence  of  the  prevailing  west 
winds,  these  masses  of  sand  move  with  a  mean  celerity  of  about  80 
feet  per  annum,  covering  forests  and  villages  in  their  progress.  A 
part  of  the  little  town  of  Mimizan  is  already  invaded,  and  it  has 
been  calculated  that  in  the  course  of  twenty  centuries,  things  pro- 
ceeding at  their  present  rate,  the  rich  territory  of  Bordeaux  will 
have  completely  disappeared.  In  their  progress  these  moving  mass- 
es of  sand  choke  up  the  beds  of  rivers,  and  increase  the  disastrous 
effects  they  produce  otherwise  by  causing  formidable  inundations. 

The  sands  of  the  Gulf  of  Gascony,  like  those  of  Holland  and  the 
Low  Countries,  are  not  altogether  without  moisture ;  a  very  short 
way  below  the  surface  they  are  moist,  and  even  present  a  certain 
degree  of  cohesion.  This,  in  fact,  might  have  been  predicated,  for 
otherwise  the  wind  which  brings  them  from  the  sea  would  have  dis- 
persed them  in  clouds  of  dust  and  to  great  distances ;  but  no  such 
dispersion  takes  place.  Downs  advance  slowly,  at  the  rate  already 
indicated,  and  by  rolling  over,  as  it  were,  upon  themselves.  The 
sand  driven  by  the  wind  creeps  up  on  the  flanks  of  the  ridges  as 
upon  an  inclined  plane  ;  after  having  got  over  the  summit  of  the 
hillocks  already  formed,  it  falls  down  the  opposite  slope,  and  accu- 
mulates at  the  base.  The  action  of  the  wind  is  only  exerted  upon 
so  much  of  the  sand  as  is  rendered  loose  and  moveable  by  its  dry- 
ness ;  but  the  moist  part  is  exposed,  dried,  and  swept  away  in  its 
turn  ;  in  this  way  the  whole  mass  of  sand  which  was  at  first  deposit- 
ed upon  the  west  aspect  of  the  hillocks  is  carried  to  the  east,  where 
it  is  in  the  shelter.  By  this  process,  under  the  influence  of  a  wind 
fvhich  blew  steadily  for  six  days,  a  hillock  has  been  seen  to  advance 
towards  the  interior  of  the  country  through  a  space  of  3|  feet.f 

The  moisture  contained  in  the  sand  proceeds  from  the  rains,  from 
the  surface  water  that  filters  through  it  and  displaces  the  salt  water 
which  impregnated  it  originally.  The  very  slight  trace  of  sea-salt 
that  finally  remains  it  it  has  no  unfavorable  influence  on  vegeta- 
tion. 

Once  aware  of  the  fact  that  certain  plants  throve  in  the  sands  of 
downs,  Bremontier  saw  that  they  alone  were  capable  of  staying  their 
progress  and  consolidating  them.  The  grand  object  was  to  get 
plants  to  grow  in  moving  sand,  and  to  protect  them  from  the  violent 
winds  which  blow  oflf  the  ocean,  until  their  roots  had  got  firm  hold 
of  the  soil. 

•  Annals  of  French  Agriculture,  vol.  xxvii.  p.  145. 
t  D'Aubiiisson,  Geognosy,  vol.  ii.  p.  467. 


ARREST  OF  MOVING  SANDS.  237 

Downs  do  not  bound  the  ocean  like  beaches.  From  the  base  of 
the  first  hillocks  to  the  line  which  marks  the  extreme  height  of  spring 
tidee,  there  is  always  a  level  over  which  the  sand  sweeps  without 
pausing.  It  was  upon  this  level  space  that  Bremontier  sowed  his 
first  belt  of  pine  and  furze  seeds,  sheltering  it  by  means  of  green 
branches,  fixed  by  forked  pegs  to  the  ground,  and  in  such  a  way 
that  the  wind  should  have  least  hold  upon  them,  viz.,  by  tu.-ning  the 
lopped  extremities  towards  the  wind.  Experience  has  shown  that 
by  proceeding  thus,  fir  and  furze  seeds  not  only  germinate,  but  that 
the  young  plants  grow  with  such  rapidity,  that  by  and  by  they  form 
a  thick  belt,  a  yard  and  more  in  height.  Success  is  now  certain. 
The  plantation  so  far  advanced,  arrests  the  sand  as  it  comes  from 
the  bed  of  the  sea,  and  forms  an  effectual  barrier  to  the  other  belts 
that  are  made  to  succeed  k  towards  the  interior.  When  the  trees 
are  five  or  six  years  of  age,  a  new  plantation  is  made  contiguous  to 
the  first  and  more  inland,  from  200  to  300  feet  in  breadth,  and  so 
the  process  is  carried  on  until  the  summits  of  the  hillocks  are  gradu- 
ally attained. 

It  was  by  proceeding  in  this  way  that  Bremontier  succeeded  in 
covering  the  barren  sands  of  the  Arrachon  basin  with  useful  trees 
Begun  in  1787,  the  plantations  in  1809  covered  a  surface  of  between 
9,000  and  10,000  square  acres.  The  success  of  these  plantations 
surpassed  all  expectation ;  in  sixteen  years  the  pine  trees  were  from 
thirty-five  to  forty  feet  in  height.  Nor  was  the  growth  of  the  furze, 
of  the  oak,  of  the  cork,  of  the  willow,  less  rapid.  Bremontier  show- 
ed for  the  first  time  in  the  annals  of  human  industry,  that  moveable 
sands  might  not  only  be  stayed  in  their  desolating  course,  but  actu- 
ally rendered  productive.  Like  all  other  inventors,  this  benefactor 
of  humanity  was  soon  the  object  of  jealousy  among  his  contempora- 
ries. Doubts  were  of  course  entertained  at  first  of  the  possibility 
of  consolidating  the  moving  sands  of  downs  ;  and  when  this  was  de- 
monstrated, the  honor  of  originality  was  denied  him.  The  ingenious 
engineer  defended  himself  with  moderation,  and  demanded  an  in- 
quiry ;  in  the  course  of  which  it  was  satisfactorily  proved  that  noth- 
ing of  the  same  kind  had  been  attempted  by  others  previously  to  the 
year  1788.  The  labors  of  Bremontier  must  be  regarded  as  another 
of  those  remarkable  struggles  which  the  industry  of  man  has  suc- 
cessfully waged  with  the  elements. 


CHAPTER    V. 


OF    MANURES. 


Whatever  may  be  its  constitution  and  physical  properties,  land 
yields  lucrative  crops  only  in  proportion  as  it  contains  an  adequate 
quantity  of  organic  matter  in  a  more  or  less  advanced  state  of  de- 
composition.    There  are  favored  soils  in  which  this  matter,  desig 


238  MANtTRES. 

nated  by  the  name  of  humus^  or  mould,*  exists  by  nature,  while  there 
are  others,  and  they  form  the  majority,  which  are  either  totally  des- 
titute of  it,  or  contain  it  but  in  insignificant  proportion.  To  become 
productive,  these  soils  require  the  intervention  of  manure  ;  for  this 
"here  is  no  substitute,  neither  the  labor  which  breaks  them  up,  not 
the  climate  which  so  powerfully  promotes  their  fecundity,  nor  tho 
salts  and  alkalies  which  are  such  useful  auxiliaries  of  vegetation. 
Not  that  land  entirely  destitute  of  organic  remains  is  incapable  of 
producing  and  developing  a  plant.  We  have  already  seen  that  the 
atmosphere,  light,  heat,  and  moisture,  suffice  for  its  existence  ;  but 
in  such  a  condition,  vegetation  is  slow  and  often  imperfect ;  nor 
could  agricultural  industry  be  advantageously  applied  to  a  soil  which 
approached  so  near  to  absolute  sterility. 

Plants,  considered  in  their  entire  (?Onstitution,  contain  carbon, 
water,  (completely  formed,  or  in  its  elements,)  azote,  phosphorus, 
sulphur,  metallic  oxides  united  to  the  sulphuric  and  phosphoric  acids, 
chloildes,  and  alkaline  bases  in  combination  with  vegetable  acids ; 
many  of  these  elements  form  no  part  of  the  atmosphere,  and  are 
necessarily  derived  from  the  soil.  Moreover,  the  manures  most 
generally  made  use  of  are  nothing  but  the  detritus  of  plants,  or  the 
remains  or  excretions  of  animals,  including  by  the  very  fact  of  their 
origin  the  whole  of  the  elements  which  constitute  organized  beings; 
and  although  it  is  very  probable  that  certain  tribes  of  plants  are  more 
adapted  than  others  to  appropriate  the  azote  or  the  ammoniacal  va- 
pors of  the  atmosphere,  experience  proves  that  azotized  organic  re- 
mains contribute  in  the  most  efficacious  manner  to  the  fertility  of  the 
soil.  Besides,  we  are  far  from  being  able  to  affirm  that  the  carbon 
of  plants  is  derived  from  the  carbonic  acid  of  the  atmosphere. 
Doubtless  this  acid  is  its  principal  source ;  but  it  is  possible  that 
certain  elements  of  carburetted  dungs  may  be  directly  assimilated. 

The  writers  who  have  treated  of  manures,  have  generally  formed 
them  into  two  grand  classes  : 

1st.  Manures  of  organic  origin,  in  which  are  again  found  all  the 
elements  of  the  living  matter. 

'2d.  Mineral  manures,  saline  or  alkaline,  which  are  particularly 
designated  under  the  name  of  stimulants,  thus  ascribing  to  them  the 
faculty,  purely  gratuitous,  of  facilitating  the  assimilation  of  the  nu- 
triment which  plants  find  in  dung,  and  of  stimulating  and  exciting 
their  organs.  Such  a  distinction  has  no  real  foundation,  and  nothing 
shows  so  much  how  scanty  our  knowledge  upon  this  subject  has 
hitherto  been  as  this  tendency  in  the  ablest  minds  to  connect  vege- 
table nutrition  with  the  feeding  of  animals. 

All  the  agents  employed  by  the  agriculturist  to  restore,  preserve, 
and  augment  the  fecundity  of  the  soil,  1  shall  term  Manures.  In 
my  view  gypsum,  marl,  and  ashes  are  manures,  as  much  as  horse- 
dung,  blood,  or  urine  ;  all  contribute  to  the  end  proposed  in  em])loy- 
ing  them,  which  is  the  increase  of  vegetable  production.     The  hest 

*  Mould,  or  vegetable  earth,  as  the  word  is  generally  used,  is  not  exactly  humua  r 
but  as  it  derives  its  principal  q'ialities  from  the  presence  of  the  humus  of  the  chemist 
\  iball  eenerally  employ  the  terms  as  synonymous.— Eng.  Ed. 


DECAY   OF   ORGANIC    MATTERS.  239 

manure,  that  which  is  in  most  general  use,  is  precisely  that  which 
by  its  complex  nature  contains  all  tlire  fertilizing  principles  required 
in  ordinary  tillage. 

Particular  cultures  may  demand  particular  manures  ;  but  the  stand- 
ard manure,  such  as  farm  dung,  for  example,  when  it  is  derived  from 
good  feeding,  supplied  to  animals  with  suitable  and  abundant  litter, 
affords  all  the  pr'inciples  necessary  to  the  development  of  plants ; 
such  manure  contains  at  once  all  the  usual  elements  which  enter 
into  the  organization  of  plants,  and  all  the  mineral  substances  which 
are  distributed  throughout  their  tissues;  in  fact,  carbon,  azote,  hy- 
drogen, and  oxygen  are  found  therein  united  with  the  phosphates, 
sulphates,  chlorides,  &c. 

In  order  to  be  directly  efficacious,  every  manure  must  present 
this  mixed  composition.  Ashes,  gypsum,  or  lime  spread  upon  bar- 
ren land,  would  not  improve  it  in  any  sensible  degree  ;  azotized  or- 
ganic matter,  absolutely  void  of  saline  or  earthy  substances,  would 
probably  produce  no  better  effect ;  it  is  the  admixture  of  these  two 
classes  of  principles,  of  which  the  first  is  derived  definitively  from 
the  atmosphere,  while  the  second  belongs  to  the  solid  part  of  the 
globe,  which  constitutes  the  normal  manure  that  is  indispensable  to 
the  improvement  of  soils. 

Dead  organic  matter,  subjected  to  the  united  influence  of  heat,  of 
moisture,  and  of  contact  with  the  air,  undergoes  radical  modifica- 
tions, and  passes  by  a  regular  course  of  transformation  into  a  con- 
dition more  and  more  simple.  The  tissues,  so  long  as  they  form  a 
part  of  the  animated  being,  are  protected  against  the  destructive  ac- 
tion of  the  atmospheric  agents  ;  in  plants  and  animals  this  protec- 
tion is  not  extended  beyond  the  period  of  th^ir  existence ;  destruc- 
tion commences  with  death,  if  the  accessory  circumstances  are  suf- 
ficiently intense  ;  and  then  ensue  all  the  phenomena  of  decomposi- 
tion, of  that  putrid  fermentation  which,  at  the  expense  of  the  primi- 
tive elements  of  the  organized  being,  generates  bodies  more  stable 
and  less  complicated  in  their  constitution,  and  which  present  them- 
selves in  the  gaseous  and  crystalline  conditions,  forms  which  are 
affected  by  the  inorganic  bodies  of  nature  in  general. 

The  mineral  substances  which  had  been  taken  up  in  the  organiza- 
tion become  freed,  and  are  thus  again  restored  to  the  earth.  The 
organized  substances  which  change  the  most  rapidly,  are  precisely 
those  into  which  azote  enters  as  a  constituent  principle.  Left  to 
themselves,  whether  in  solution  or  merely  moistened,  these  sub- 
stances exhibit  all  the  characteristic  signs  of  putrefaction  ;  they  ex- 
hale an  insupportable  odor ;  and  the  result  of  their  total  and  com- 
plete decomposition  is  finally  the  production  of  ammoniacal  salts. 
The  water  wherein  the  phenomenon  is  accomplished  facilitates  it 
not  only  by  weakening  cohesion  and  enabling  the  molecules  to  move 
more  freely,  but  it  assists  also  by  the  very  affinity  which  each  of  its 
own  principles  bears  to  the  elements  of  the  substance  subjected  to 
the  putrescent  fermentation.  Proust  observed  that  during  the  de- 
composition of  glute  1  immersed  in  water,  a  mixture  of  carbonic 
acid  and  of  pure  hydrogen  gas  is  disengaged,  i  phenomenon  which 


240  MANURES. 

he  explains  by  the  decomposition  of  the  water ;  at  the  same  time 
are  produced  ammoniacal  sahs,  among  which  are  acetates  and  lac- 
tales,  whose  acids  are  generated  by  the  very  act  of  fermentation. 
As  a  striking  example  of  the  agency  of  water  in  the  transit  of  azote 
into  the  ammoniacal  state  in  a  quarternary  compound,  we  may  tak*» 
the  putrefaction  of  urea. 

Urea  is  found  in  the  urine  of  man  and  of  quadrupeds  ;  its  compo 
sition,  according*  to  M.  Dumas,  is  : 

Carbon...   20.0 

Hydrogen 6.6 

Oxygen 26.7 

Azote .••46.7 

100.0 

The  animal  substances  dissolved  in  urine,  as  the  mucus  of  the 
bladder,  &c.,  undergo,  on  contact  with  the  air,  a  modification  which 
causes  them  to  act  upon  urea  like  ferments.  By  their  influence  the 
elements  of  water  react  upon  this  substance,  and  transform  it  into 
carbonate  of  ammonia. 

Carbonate  of  ammonia  is  composed  of : 

Carbonic  acid  56.41,  containing       j  Sxy^g^en .'.'." .'  !.*.*.*!!*.*!!.' .'.".'.4l!^ 


and 


Hydrogen 7. 


Ammonia  43.59,  containing      .       j  Azote 35.90 

But  100  of  urea  have  been  found  to  produce  by  fermentation  130 
of  carbonate  of  ammonia. 

Carbon.  Hydrog^en.  Oxygen,  Aiote. 

Previous  to  fermentation,  100  of  urea  )        20  00  6  60            2  67  46.7 

contains  ....}' 

After  fermentation,  130  of  carbonate  J        2000  10  00            533  46  7 

of  ammonia  contains       .       .         J            '  '  '_  '__ 

Difference         0.0  3.4             26.6             0.0 

So  that  during  its  transformation,  the  urea  has  gained  3.4  of  hy 
drogen,  and  26.6  of  oxygen. 

In  water  the  hydrogen  is  to  the  oxygen  as  1  to  8.  (:  :  1  :  8.) 

Now  it  is  precisely  in  this  proportion  that  hydrogen  and  oxygfti' 
are  found  to  be  acquired  by  the  urea  in  passing  into  the  state  of  ea* 
bonate  of  ammonia ;  whence  it  follows  that  the  elements  of  wave 
are  fixed  in  the  process. 

The  putrefaction  of  azotized  substances  is  far  from  always  pre- 
senting results  equally  precise  ;  most  frequently  in  decomposing 
they  pass  through  a  series  of  changes,  still  very  obscure,  before 
they  attain  their  ultimate  limit,  viz.  the  production  of  ammoniacal 
salts.  Thus  from  putrefying  caseum  diffused  in  water,  M.  Braconnot 
obtained,  among  other  products  and  ammoniacal  salts,  a  very  remark- 
able substance  which  he  calls  aposepedine. 

Aposepedine  when  purified  is  a  white  crystalline  substance,  soluble 
in  water  and  in  alcohol,  capable  of  combination  with  the  metallic 
oxides  ;  azote  is  one  of  its  elements. 

This  substance,  although  engendered  by  the  act  of  putrefaction,  is 
rsvertheless  itself  capable  of  putrefying  and  giving  birth  to  the  last 
products  of  the  spontaneous  decomposition  of  azotized  matter. 

One  of  the  most  striking  characteristics,  at  least  that  which  is 


DECAY   OF   ORGANIC   MATTERS.  241 

most  readily  remarked,  is  the  fetid  odor  which  animal  substances 
exhale  during  putrefaction.  It  is  not  always  the  smell  of  ammonia 
which  preciominates ;  that  of  sulphuretted  hydrogen  gas  is  often 
very  strong ;  yet  that  is  not  the  emanation  which  is  most  repulsive  : 
miasmata  and  nauseous  principles  are  also  developed  which  seem  to 
be  the  changed  matter  itself  carried  away  by  the  gases  that  are  dis- 
engaged. 

Sulphur,  like  phosphorus,  is 'almost  always  a  constituent  of  or- 
ganic bodies ;  its  minute  proportion,  however,  would  be  insufficient 
to  give  out  the  hepatic  odor  so  intense  as  we  often  find  it  during 
putrefaction.  The  production  of  sulphuretted  hydrogen  is  connect- 
ed with  the  very  curious  fact,  first  appreciated  by  M.  O.  Henri, 
that  sulphates  dissolved  in  a  medium  impregnated  with  azotized 
matter  in  decomposition,  do  themselves  undergo  an  actual  reduction, 
pass  into  the  state  of  sulphurets,  and  immediately  give  out  sulphuret- 
ted hydrogen,  either  by  the  action  of  the  carbonic  acid  of  the  at 
mosphere,  or  by  that  which  is  formed  during  the  putrefaction  of  the 
organic  matter.  It  is  by  a  similar  action  exerted  upon  sulphate  of 
lime  that  M.  Henri  explains  the  origin  of  the  sulphureous  waters  of 
Enghien,  near  Paris ;  and  M.  Fontan  in  his  important  work  on  min- 
eral waters  has  generalized  this  explanation. 

The  causes  of  the  destruction  of  sulphates  under  such  circum- 
stances if^  easily  understood.  During  the  decomposition  of  organiz- 
ed substances,  the  carbon  belonging  to  them  forms  carbonic  acid  gas ; 
by  combining  both  with  the  oxygen  of  the  substances  themselves, 
and  with  the  oxygen  of  the  water,  it  is  probable  that  the  oxygen  of 
the  sulphuric  acid  contributes  equally  to  this  formation,  and  that  the 
sulphur  is  liberated. 

The  hydrogen  of  the  decomposed  water,  as  well  as  that  of  the 
solid  matter,  in  contact  with  sulphur  in  the  nascent  state,  combines 
with  it  to  form  sulphuretted  hydrogen,  which  straightway  reacts 
upon  the  base  of  the  sulphate,  producing  from  it,  as  we  know,  water 
and  a  metallic  sulphuret.  This  sulphuret  being  unable  to  exist  when 
exposed  to  the  continued  disengagement  of  carbonic  acid  gas  which 
takes  place  in  the  centre  of  the  mass  in  putrefaction,  yields,  as  a 
definite  result,  a  carbonate  on  the  one  part,  and  sulphuretted  hydro- 
gen on  the  other. 

The  faculty  which  azotized  organic  bodies  possess  of  undergoing 
spontaneous  decomposition  in  presence  of  water,  and  under  the  in- 
fluence of  heat,  seems  to  depend  upon  the  tendency  which  azote  has 
to  unite  with  hydrogen  in  order  to  form  ammonia. 

This  tendency  is  perhaps  the  determining  cause  of  the  phenome- 
non of  fermentation  taken  in  the  most  general  acceptation  of  the 
term.  Organic  bodies  void  of  azote  decompose  less  easily,  and  the 
kind  of  alteration  which  they  undergo  from  the  action  of  water  and 
air,  differs  in  many  respects  from  the  putrefaction  of  azotized  mat- 
ter. Of  this  the  difficulty  experienced  in  effecting  the  fermentation 
of  vegetable  substances  is  a  proof  Nevertheless,  the  vegetable  re- 
fuse which  goes  to  the  dunghill,  all  without  exception,  contains  azo- 
tized elements,  often,  it  is  true,  in  extremely  minute  proportions ; 

21 


343  MANURES. 

but  we  Icnow  that  there  is  no  example  of  a  vegetable  organic  tissas 
from  which  they  are  completely  excluded. 

The  refuse  of  plants,  the  most  amply  endowed  with  azote,  such  as 
cabbage,  beet-root,  beans,  &c.,  are  certainly  those  which  are  sus- 
ceptible of  the  most  rapid  and  complete  putrid  fermentation  ;  straw, 
on  the  contrary,  when  alone,  undergoes  it  slowly  and  imperfectly, 
the  small  quantity  of  the  azotic  principle  which  it  contains  is  chang* 
ed,  and  reacts  upon  the  ligneous  particles  which  surround  it ;  but 
the  effect  is  soon  arrested,  and  even  ceases  entirely,  unless  substances 
richer  in  azote  concur.  The  woody  matter  of  the  straw  is  exactly 
in  the  condition  of  sugar  which  has  not  had  a  dose  of  ferment  suf- 
ficient for  its  total  transformation  into  alcohol. 

Most  organized  substances,  whether  they  belong  to  the  animal  or 
vegetable  kingdom  when  placed  in  certain  conditions,  undergo  the 
profoundest  changes  from  the  action  of  hydrogen  ;  these  alterations 
ought  to  be  studied  with  all  the  more  care,  because  in  practical 
agriculture  we  are  interested  successively  in  fostering  or  preventing 
the  causes  which  produce  them,  according  as  our  object  is  to  accele- 
rate the  decomposition  of  vegetable  refuse  for  manure,  or  to  adopt 
the  precautions  which  experience  suggests,  in  order  to  preserve 
the  produce  of  our  harvests  unchanged.  Organic  substances  moist- 
ened and  exposed  to  the  air  under  a  temperature,  the  minimum  of 
which  (I  believe  after  several  experiments)  may  be  fixed  at  48°  or  50" 
F.,  seize  upon  the  oxygen  and  absorb  it,  in  part,  in  order  to  form  water 
with  their  hydrogen,  and  carbonic  acid  with  their  carbon.  When 
these  substances  are  accumulated  in  a  mass  sufficiently  great,  the 
heat  produced  is  not  rapidly  dissipated,  the  temperature  rises,  and 
promotes  the  reaction  to  such  a  degree  as  to  produce  active  burning, 
a  conflagration,  in  place  of  the  slow  combustion  manifested  at  first. 
It  is  not  very  unusual  to  see  hay,  which  had  been  gathered  in  too 
damp  a  condition,  take  fire  in  the  stack ;  and  the  high  temperature 
acquired  by  wet  rags  placed  in  the  fermenting  vats  of  paper  mills, 
and  the  copious  production  of  carbonic  acid  which  results,  show  that 
we  are  right  in  assimilating  this  kind  of  action  to  the  phenomenon 
of  combustion.  This  sluggish  combustion  is  not  peculiar  to  azotized 
organic  substances  :  it  takes  place  equally  in  those  destitute  of  azote. 
The  alteration  of  organic  matters,  the  combustion  which  goes  on  at 
a  low  temperature  by  the  action  of  the  air,  difi'ers  in  its  results  from 
the  decomposition  which  is  effected  in  the  midst  of  a  liquid  mass. 
We  have  seen,  for  example,  that  gluten  fermenting  under  water, 
disengages  hydrogen  gas.  Now  Berthollet  has  established,  and 
Saussure  has  confirmed  his  observations,  that  an  azotized  body  in 
putrefaction,  the  whole  of  whose  parts  are  in  contact  with  the  air, 
never  contributes  either  hydrogen  gas  or  azote  to  the  confined  at- 
mosphere in  which  it  is  placed  ;  and  on  the  other  hand,  Saussure 
has  shown,  that  organic  substances  which  do  not  emit  hydrogen  gas 
during  their  spontaneous  decomposition  in  a  medium  void  of  oxygen, 
do  not  alter  the  volume  of  an  atmosphere  of  which  this  gas  forms  a 
purt;  on  the  contrary,  these  sub  tances  condense  oxygen  as  soon  af 


DECAY   OF    ORGANIC    MATTERS.  243 

they  attain  that  stage  of  their  alteration  in  which  they  give  out  hy 
drogen. 

In  pursuing  with  persevering  sagacity  the  study  of  putrefaction, 
M.  de  Saussure  discovered  the  cause  of  this  condensation  ;  it  con- 
sists in  the  fact,  that  an  organic  suhstance  in  course  of  spontaneous 
decomposition,  acts  in  some  respects  like  the  platina  sponge  placed 
in  a  mixture  of  oxygen  and  hydrogen  gas ;  we  know  that  platina 
recently  heated  and  introduced  into  a  mixture  of  these  two  gases, 
determines  their  union  in  the  proportions  required  to  constitute  water. 
Nowr  by  substituting  for  the  metal  some  moistened  seeds,  previously 
deprived  of  their  germinating  faculty,  the  same  effect  is  produced  : 
the  two  gases  combine  until  one  of  the  two  entirely  disappears. 
When  this  combustion  of  hydrogen,  proceeding  from  the  decomposi- 
tion of  organic  substances,  takes  place  in  the  body  of  the  atmosphere 
which  contains  azote,  it  is  possible  that  a  minute  quantity  of  ammonia 
may  be  produced  together  with  water  ;  nor  is  it  going  too  far  to 
suppose,  that  manures  very  slightly  azotized,  take  up  azote  from 
the  atmosphere  during  their  fermentation;  that  during  the  act  of 
vegetation  itself,  the  hydrogen  proceeding  from  the  decomposed 
water,  or  yet  more,  that  which  makes  part  of  the  essential  oils  form- 
ed by  plants,  may,  in  oxidating  afresh,  introduce  atmospheric  azote 
into  their  composition. 

Dead  organized  matter,  such  as  wood,  straw,  or  leaves,  exposed 
to  wet,  and  for  a  long  time  to  the  action  of  the  air,  ends  by  becom- 
ing transformed  into  a  brown  substance,  which  when  damped  is  al- 
most black,  which  falls  to  powder  when  dry,  and  which  is  commonly 
known  by  the  name  of  humus  or  mould. 

This  is,  so  to  speak,  the  last  term  of  the  decomposition  of  organic 
matter ;  mould  appears  to  belong  already  to  the  mineral  kingdom  ; 
and  whatever  may  be  the  diversity  of  its  origin,  it  presents  a  suf- 
ficient number  of  peculiar  characteristics  to  be  considered  a  distinct 
substance.  In  fact,  the  atmosphere  continues  to  exert  its  action 
upon  mould  ;  its  inflammable  elements  are  dissipated  by  a  slow  and 
imperceptible  combustion,  giving  place  to  water  and  carbonic  acid. 
But  in  this  ulterior  decomposition,  those  fetid  products  which  char- 
acterize putrid  fermentation  are  no  longer  observed. 

Wet  saw-dust,  placed  for  some  weeks  in  an  atmosphere  of  oxygen, 
forms  a  certain  quantit}'  of  carbonic  acid,  and  the  volume  of  the  gas 
does  not  perceptibly  diminish.  The  wood  at  the  surface  acquires  a 
deep-brown  color.  Several  experiments  made  by  Saussure,  prove 
that  dead  wood  does  not  absorb  the  oxygen  gas  of  the  atmosphere  ; 
it  transforms  it  into  carbonic  acid,  and  the  action  takes  place  as  if 
the  carbon  of  the  organic  matter  alone  experienced  the  effects  of  the 
oxygen  ;  for  the  gaseous  volume  remains  the  same.  The  loss,  how- 
ever, undergone  by  the  ligneous  fibre,  during  its  exposure  to  the  air, 
is  greater  than  it  ought  to  be  if  carbon  alone  were  eliminated :  whence 
Saussure  concludes,  that  while  the  woody  matter  loses  carbon,  it 
also  lets  some  of  its  constituent  water  escape. 

As  a  consequence  of  these  observations,  the  relative  proportion 
of  carbon  ought  to  augment  in  the  humid  wood  changed  by  the  ac 


S44  MANURES. 

tion  of  the  atmosphere,  since  we  have  established  that  by  this  action 
the  woody  fibre  suffers  loss  in  the  elements  of  water  besides  what  it 
loses  in  carbon.  This  is  confirmed  by  the  following  analyses.  The 
first,  made  upon  some  oak  wood,  previously  purified  by  washing  ia 
water  and  in  alcohol,  we  owe  to  Messrs.  Thenard  and  Gay-Lussac; 
the  succeeding  one  to  Messrs.  Meyer  and  Will : 

Oak  wood.  Id.  rotten.  Id.  rotten. 

Carbon 52-5  .53.6             5«.2 

Hydrogen  and  oxygen,  water ■•47..'>  46.4            43-8 

100.0  100.0  100.0 

Wood  decomposed  under  water,  without  being  in  direct  contact 
with  the  air,  undergoes  a  different  modification  ;  it  is  blanched  in- 
stead of  blackened,  and  the  carbon  far  from  increasing  is  diminished. 
Saussure  thinks  that  this  kind  of  alteration  depends  mainly  on  the 
loss  of  the  soluble  and  coloring  principles  of  the  wood,  principles 
containing  more  carbon  than  the  ligneous  matter  itself:  so  that  pure 
woody  fibre  exposed  wet  to  the  action  of  the  air  would  yield  pro- 
ducts analogous  to  those  which  result  from  its  decomposition  under 
water. 

The  damp  linen  rags  which  are  fermented  in  paper  manufactories 
afford  a  product  which  is  white,  and  but  slightly  coherent.  The 
mass,  which  heats  successively  during  the  operation,  loses  about  20 
per  cent,  of  its  original  weight.  This  is  exactly  what  takes  place 
in  wood  decayed  by  the  alternate  action  of  water  and  air,  namely,  it 
becomes  white  and  extremely  friable. 

Some  oak  arrived  at  this  stage  of  decomposition  contained,  ac- 
cording to  Liebig : 

Carbon 47-6 

Hydrogen 6.2 

Oxygen 44.9 

Ashes 1.3 

100.0 

Compared  with  the  composition  of  oak  wood  when  sound,  thesd 
numbers  show  that  during  its  modification  the  wood  has  lost  carbon, 
and  that  it  has  gained  hydrogen.  The  elements  of  water  must  ne- 
cessarily have  intervened,  and  become  fixed  during  the  reaction. 
Ligneous  fibre  decaying  under  water  is  not  thereby  completely  pro- 
tected from  the  atmosphere.  Water  always  holds  some  air  in  solu- 
tion, and  the  oxygen  of  that  air  reacts  exactly  as  if  it  were  in  the 
gaseous  state. 

Upon  all  the  phenomena  of  decomposition  connected  with  fermen- 
tation, with  putrefaction,  or  with  dilatory  combustion,  heat  exerts 
an  influence  which  has  certainly  not  been  sufficiently  appreciated. 
Organic  bodies  sunk  in  a  large  mass  of  water  are  not  exposed  to 
changes  of  temperature  so  various  and  abrupt  as  when  they  are 
placed  in  the  atmosphere ;  their  decomposition  is  more  gradual, 
more  uniform,  and  the  soluble  materials  which  they  contain,  or  which 
are  the  result  of  the  alteration  they  are  undergoing,  are  in  a  great 
measure  dissolved.    Temperature  may  also  produce  great  difference! 


DECAY  OF  ORGANIC  MATTERS.  24S 

m  the  final  lesiilt  of  the  decomposition.  Peat,  which  is  derived,  aa 
we  know,  from  the  slow  decomposition  of  submerged  plants,  does  not 
appear  to  be  formed  in  the  swamps  of  warm  climates  ;  it  has,  per- 
haps, never  been  encountered  in  the  stagnant  waters  of  the  equinoc- 
tial regions ;  there  the  woody  fibre  appears  to  be  totally  dissipated 
in  carbonic  acid  gas,  and  in  marsh  gas,  the  probable  source  of  the 
insalubrity  of  those  countries.  Lakes  with  peat  bottoms  are  not 
found  except  on  the  very  high  table-lands  of  the  Andes,  in  localities 
where  the  mean  temperature  does  not  exceed  49°  or  50°  F. 

The  alkalies  are  powerful  agents  in  the  decomposition  of  certain 
organic  substances,  whether  in  determining  or  in  accelerating  it. 
There  are  some,  indeed,  which  experience  no  change  without  their 
intervention,  whatever  may  be  the  other  conditions  favorable  to  de- 
composition. Thus,  according  to  M.  Chevreul,  many  coloring  sub- 
stances may  be  preserved  in  solution  almost  indefinitely,  without 
change,  in  contact  with  gallic  acid  ;  but  the  presence  ot  a  very  small 
quantity  of  free  alkali  suffices  for  their  immediately  acquiring  the 
power  of  absorbing  oxygen,  and  at  the  same  time  of  acquiring  a  brown 
tint.  M.  Chevreul  observed  that  3.087  grs.  of  hematine  dissolved 
in  potash  will  absorb  3.857  grs.  of  oxygen  in  forming  0.925  of  car- 
bonic acid.  The  oxygen  which  enters  into  the  carbonic  acid,  there- 
fore, represents  nothing  like  the  quantity  which  was  fixed  by  the 
solution,  and  it  is  almost  certain  that  this  gas  likewise  reacted  upon 
the  hydrogen  of  the  coloring  matter.  The  use  of  the  alkalies  for 
accelerating  the  destruction  of  organized  matter  has  been  long  known 
to  agriculturists. 

Straw,  fern,  and  the  ligneous  parts  of  plants  are  sometimes  strat- 
ified with  quick-lime,  in  order  to  facilitate  their  disintegration,  and 
consequently  their  decomposition.  The  utility  of  this  old  practice 
cannot  be  disputed  while  confined  within  certain  limits ;  but  it  is 
often  abused  ;  for  it  is  beyond  doubt  that  alkalies  mingled  indiscrim- 
inately with  manure  become  in  reality  more  injurious  than  advan- 
tageous for  the  end  proposed  in  their  introduction. 

The  appearance  of  a  certain  brown  substance,  little  soluble  in 
water,  but  easily  dissolving  in  alkalies,  is  a  characteristic  proper  to 
all  vegetable  matter  under  decomposition  ;  a  characteristic  which 
becomes  more  marked  as  the  decomposition  advances  towards  its 
last  stage,  namely,  the  production  of  humus.  This  substance  is 
ulmine,  which,  on  account  of  some  acid  properties  which  it  pos- 
sesses, is  also  named  ulmic  acid.  It  forms  a  part  of  mould,  and  M. 
P.  Boullay  constantly  found  it  in  the  water  of  dunghills. 

In  1797,  Vauquelin  discovered  ulmine  united  with  potash  in  the 
matter  of  the  exudation  from  the  ulcer  of  an  elm-tree. 

In  1804,  Klaproth  confirmed  this  observation.  M.  Braconnot 
succeeded  in  obtaining  ulmine  artificially  by  subjecting  woody  fibre 
to  the  action  of  alkalies.  This  substance  is  easily  procured  by 
carefully  heating  in  a  silver  capsule,  and  continually  stirring  a  mix- 
ture of  equal  parts  of  potash  and  of  saw-dust  slightly  damped.  At 
a  certain  time  the  woody  matter  softens  and  suddenly  dissolves  ;  the 
mass  then  begins  to  swell  up,  and  the  fire  is  slaked.     The  product 

3i* 


246  HUMTTS. 

obtained  dissolves  almost  totally  in  water.  The  solution  is  of  a  very 
deop  brown  color,  and  contains  as  prinjipal  ingredient  ulmine  com- 
bined with  potash  ;  the  ulmine  is  precipitated  by  the  addition  of  a 
sufficient  quantity  of  weak  sulphuric  acid.  After  having  been 
washed  and  dried,  ulmine  is  black  and  brittle,  and  resembles  jet ; 
while  still  wet,  it  reddens  turnsole  paper,  and  its  solution  in  potash 
forms  with  several  sahs,  and  by  the  way  of  double  decomposition, 
insoluble  ulmates.  M.  Peligot  assigns  to  ulmine  the  following 
composition : 

Carbon 72.3 

Hydrogen 6-2 

Oxygen .-21.5 

100.0 

Dunghills,  rotten  wood,  and  mould,  always  contain  a  brown  sub- 
stance, which  possesses  properties  very  similar  to  those  which  char- 
acterize ulmine  obtained  by  the  action  of  alkalies  upon  ligneous 
fibre. 

Mould  which  contains  this  ulmine  in  abundance,  and  in  the  con- 
dition most  favorable  to  vegetation,  ought  on  that  account  to  be 
examined  with  attention.  Its  history  has,  indeed,  been  so  ably  traced 
by  M.  de  Saussure,  that  science  at  the  present  day  can  add  but  little 
to  the  important  deductions  of  the  celebrated  author  of  the  Re- 
cherches  Chimiques. 

M.  de  Saussure  defines  vegetable  mould  (humus)  to  be  the  black 
substance  which  covers  dead  vegetables  after  they  have  been  long 
exposed  to  the  combined  action  of  water  and  oxygen.  His  experi- 
ments refer  to  mould  nearly  pure  ;  that  is,  separated  by  a  fine  sieve 
from  the  vegetable  remains  which  are  always  mixed  with  it ;  to 
mould  which  had  been  gathered  on  high  rocks,  or  from  the  trunks 
of  trees,  where  it  could  not  have  been  exposed  to  admixture  or  to 
any  influence,  other  than  that  of  the  spontaneous  decomposition  by 
which  it  had  been  produced.  All  the  varieties  of  mould  collected 
in  this  way  appeared  fertile,  especially  when  they  were  previously 
mixed  with  gravel,  which  supplies  support  to  the  roots  of  plants,  and 
permits  the  access  of  the  air.  That  variety,  however,  must  be  ex- 
cepted which  was  obtained  from  the  interior  of  trees,  and  had  been 
formed  in  such  a  situation  that  the  rain-water  which  entered  found 
no  free  outlet ;  the  huriius  then  contained  extractive  principles,  de- 
rived in  part  from  the  living  plant,  and  which  seemed  to  obstruct  the 
pores  of  the  vegetable  to  which  it  was  applied  as  manure. 

In  making  comparative  calcinations  in  close  vessels  of  different 
varieties  of  humus,  and  of  plants  similar  to  those  from  which  they 
had  proceeded,  and  collecting  the  charcoal  on  one  hand,  and  the 
volatile  and  gaseous  matters  on  the  other,  M.  de  Saussure  discover- 
ed that  they  contained,  for  the  same  weight,  a  larger  quantity  of 
carbon  and  of  azote  than  the  vegetables  whence  they  proceeded. 
The  larger  proportion  of  azote  in  the  humus  seems  to  imply  that 
during  their  decomposition,  vegetables  do  not  throw  off  this  element* 
but  to  this  cause  must  be  added  that  which  might  be  connected  with 
the  spoils  of  insects  which  live  in  humus. 


HUMUS.  247 

Weak  acids  have  no  other  effect  upon  humus  than  to  dissolve  out 
the  metallic,  earthy,  and  alkaline  elements  which  it  contains.  The 
more  powerful  acids,  such  as  the  sulphuric  acid,  frequently  cause  a 
disengagement  of  acetic  acid.  Alcohol  scarcely  acts  upon  humus, 
merely  dissolving  out  of  it  a  few  hundredth  parts  of  resinous  matter, 
which  probably  pre-existed  in  the  vegetable.  Potash  and  soda  dis- 
solve humus  almost  completely,  causing  an  evolution  of  ammonia. 
From  this  solution,  acids  throw  down  a  brown,  inflammable  powder, 
possessing  the  characters  which  we  have  recognised  in  ulmine.  The 
ulmine  which  is  separated  in  this  way,  is  far  from  corresponding 
with  the  weight  of  the  matter  treated  with  the  alkalies,  which  is 
evidently  due  to  the  humus  containing  principles  which  are  not  pre- 
cipitated from  the  alkaline  solution. 

A  quantity  of  humus  which  yielded  no  more  than  one  tenth  of 
ashes  by  incineration,  only  lost  one  eleventh  of  its  weight  under  re- 
peated treatments  with  boiling  water.  The  humus  thus  exhausted, 
was  exposed  in  a  moist  state  to  the  action  of  the  air  for  three  months, 
and  gave  a  new  quantity  of  soluble  matter  under  renewed  washing 
with  water;  and  the  same  effect  is  constantly  reproduced.  By  ex- 
posing moist  insoluble  humus  to  the  air,  therefore,  a  quantity  of  so- 
luble extractive  matter  is  formed.  This  matter,  obtained  by  evapo- 
rating the  water  which  is  charged  with  it,  is  not  deliquescent ;  it 
yields  ammonia  on  distillation.  The  watery  solution,  brought  to  the 
consistence  of  sirup,  is  neutral  to  re-agents,  and  its  taste  is  sensibly 
sweet. 

It  is  familiarly  known  that  the  alkaline  salts,  which  enter  into  the 
constitution  of  vegetable  juices,  but  rarely  exhibit  the  reactions  that 
are  proper  to  them  ;  the  plan  or  the  sap  must  be  dried  and  inciner- 
ated before  their  presence  can  be  ascertained.  It  is  the  same  with 
regard  to  the  salts  contained  in  humus. 

Humus,  as  I  have  already  observed,  is  the  last  term  in  the  putre- 
faction of  vegetable  organic  matter ;  its  elements  have  acquired  a 
stability  which  enables  them  to  resist  all  fermentation.  M.  de  Saus- 
sure  preserved  humus  for  a  whole  year  in  vessels  filled  with  distilled 
water,  and  plunged  in  mercury,  without  remarking  any  emission  of 
gas.  Still  it  is  unquestionable  that  the  organic  portion  of  humus  is. 
completely  destructible  when  exposed  moist  to  the  action  of  the  air; 
in  the  course  of  time  it  is  dissipated,  and  by  and  by  there  remains 
nothing  more  than  the  fixed  saline  and  earthy  matters  which  it  con- 
tained. This  fact  M.  B.  de  Saussure  had  already  perceived  from 
his  observations  upon  the  vegetable  soil  that  occurs  in  the  country 
between  San  Germano  and  Turin.  This  destructibiliiy  of  vegetable 
earth,  says  M.  de  Saussure,  sen.,  is  a  fact  without  exception  ;  and 
as  often  as  agriculturists  have  proposed  to  supply  the  place  of  ma- 
nure by  repeated  ploughings,  they  have  had  sad  experience  of  its 
truth  :  the  soil  is  gradually  impoverished,  and  fertile  fields  ultimate- 
ly become  barren.  I  may  add,  that  the  nature  of  the  climate  has  a 
vast  influence  upon  the  dissipation  of  the  fertilizing  principles  of  the 
soil,  and  that  Europeans  are  certainly  in  error  when  they  object  to 
the  superficial  ploughings  or  hoeings  which  the  land  ^  commonly 


M8  nitrificatiopt. 

receives  in  tropical  countries.  It  is  there  well  known  that  too  mnch 
stirring  of  the  soil  is  i  'ten  prejudicial  even  in  irrigated  lands,  where 
consequently  the  bad  i  ifects  cannot  be  attributed  to  too  great  a  de- 
gree of  dryness.  The  information  which  has  lately  reached  the 
Academy  of  Sciences  upon  the  agriculture,  of  the  French  posses- 
sions in  Africa,  tend  to  make  us  perceive  that  the  same  cause  pro- 
duces the  same  effects  in  Algeria,  and  that  it  is  not  without  reason 
that  the  Arabs  only  work  their  lands  that  are  preparing  for  grain 
crops,  very  superficially. 

Humus  is,  in  fact,  dissipated  by  a  process  of  slow  combustion  in 
the  air :  in  contact  with  oxygen,  it  produces  carbonic  acid,  as  is 
proved  by  the  experiments  of  M.  de  Saussure.  Pure  humus,  moist- 
ened with  distilled  water,  confined  in  bell-glasses  placed  over  me:»- 
cury,  formed  carbonic  acid,  causing  the  disappearance  of  the  oxygen 
of  the  air.  The  volume  of  the  acid  gas  formed,  corresponded  ii 
volume  with  that  of  the  oxygen  which  had  disappeared.  Humus, 
therefore,  in  contact  with  air,  gives  off  carbonic  acid,  and  the  phe- 
nomenon here  still  takes  place  as  if  carbon  were  not  alone  consumed. 
The  loss  experienced  is  greater  than  that  which  ought  to  occur  from 
the  quantity  of  carbon  which  unites  with  the  oxygen  ;  and  Saussure 
concluded  that  there  is,  at  the  same  time,  a  loss  of  the  elements  of 
water.  The  capital  fact  which  results  from  these  experiments  of 
Saussure,  the  deduction  directly  applicable  to  the  theory  of  manures 
is  this :  that  humus  is  dissipated  when  it  is  exposed  to  the  air,  and 
that  during  the  slow  combustion  which  it  undergoes,  it  is  a  constant 
source  of  carbonic  acid  gas. 

To  complete  the  views  that  may  throw  light  on  the  part  played 
by  manures,  I  have  still  to  speak  of  an  important  phenomenon  which 
occasionally  takes  place  under  the  same  conditions  as  those  that  ac- 
company the  decomposition,  the  putrefaction  of  animal  matters :  I 
mean  the  spontaneous  formation  of  nitric  acid — the  occurrence  of 
nitrification  as  it  is  called.  Nitric  acid  results  from  the  union  of 
azote  with  oxygen.  Such  at  least  is  the  constitution  of  this  acid 
when  it  is  combined  in  salts ;  but  in  its  isolated  state,  it  is  always 
united  with  a  certain  quantity  of  water.  It  has  not  yet  been  obtain- 
ed, and  it  appears  indeed  not  to  exist,  in  the  perfectly  dry  or  anhy- 
drous state.  The  azote,  therefore,  does  not  combine  directly  with 
the  oxygen  ;  there  must  be,  at  all  events,  the  intervention  of  water, 
and  to  effect  the  union  of  the  two  gases  by  means  of  the  electric 
spark,  the  mixture,  according  to  Cavendish,  must  be  moist.  Never- 
theless, the  combination  of  azote  with  oxygen  appears  to  be  singular- 
ly favored  by  the  presence  of  earthy  or  alkaline  bases,  seeing  that 
in  nature  the  nitrates  are  met  with  in  a  certain  abundance  ;  but  the 
circumstances  which  determine  their  formation  are  still  involved  in 
deep  obscurity. 

Three  distinct  origins  may  be  assigned  to  the  natural  nitrates : 
Ist.  certain  soils,  still  indifferently  studied,  show  an  efflorescence  of 
nitrate  of  potash  on  their  surface,  or  by  lixiviation  yield  large  quan- 
tities of  this  salt.  Such  is  the  gource  of  the  saltpetre  which  is  im- 
ported from  India. 


PRODUCTION    OF    NITRE    AND    NITRATES.  249 

According  to  M.  Proust,  the  soil  of  certain  localities  in  the  neigh- 
borhood of  Saragossa  is  an  inexhaustible  mine  of  saltpetre.  I  have 
myself  seen,  near  Latacunga,  a  short  way  from  Quito,  upon  a  soil 
formed  of  trachytic  debris,  a  similar  production  of  nitre  taking  place 
as  it  were  under  my  eyes. 

2d.  On  the  coast  of  Peru,  in  the  desert  of  Tarapaca,  at  a  short 
distance  from  the  port  of  Iquique,  and  in  an  argillaceous  soil  of  ex- 
tremely recent  formation,  there  are  numerous  stratified  deposites  of 
nitrate  of  soda,  analogous  to,  and  perhaps  contemporaneous  with,  the 
deposites  of  common  salt  which  are  worked  upon  the  same  coast,  in 
the  desert  of  Sechura,  near  the  equator.  This  is,  so  far  as  I  know, 
the  only  instance  of  a  nitrate  being  dug  out  of  the  bowels  of  the 
earth  as  a  mineral  mass.  The  nitrate  of  soda  of  Tarapaca,  reacr.es 
Europe  at  the  present  time  in  large-  quantities,  and  supplies  the 
place  of  nitrate  of  potash  in  many  chemical  processes.  Various  ex- 
periments have  also  been  made  upon  the  value  of  the  salt  as  a  ma- 
nure ;  but  at  present  these  experiments  have  been  very  contradic- 
tory, and  further  experience  seems  necessary  before  any  definitive 
judgment  can  be  come  to  on  the  matter. 

3d.  The  greater  number  of  the  soils  that  are  exposed  to  animal 
emanations — heaps  of  rubbish  proceeding  from  buildings  that  have 
been  long  inhabited,  the  soil  of  stables,  cow-houses,  cellars,  &c., 
almost  always  contain  a  quantity  of  nitrates.  In  countries  where 
rain  seldom  falls,  and  where  consequently  these  salts,  which  are  ex- 
tremely soluble,  can  accumulate  in  the  soil,  in  Egypt,  for  example, 
the  ruins  of  ancient  cities  are  at  the  present  time  true  nitre-beds. 
It  is  with  the  formation  from  nitre  in  such  circumstances  that  we 
feel  particularly  interested.  The  presence  of  the  salt  is  frequently 
proclaimed  in  our  agricultural  operations ;  it  is  formed  during  the 
preparation  of  our  dunghills,  in  the  midst  of  our  cultivated  fields, 
and  we  discover  it  in  the  plants  which  we  gather.  We  are  by  so 
much  the  more  interested  in  discovering  its  existence,  and  in  ascer- 
taining its  mode  of  action,  as  in  the  actual  state  of  our  knowledge  we 
are  still  unable  to  say  whether  or  no  nitre  is  an  auxiliary  in  the 
phenomena  of  vegetation,  and  contributes  to  the  production  of  the 
azotized  principles  which  enter  into  the  organization  of  plants. 

To  have  nitrates  formed,  the  presence  of  azotized  organic  matter 
is  not  sufficient ;  it  is  further  necessary  that  this  matter  during  its 
decomposition  be  in  contact  with  alkaline,  calcareous,  or  magnesian 
carbonates.  It  has  been  observed  that  rocks  of  a  crystalline  struc- 
ture do  not  nitrify  so  readily  when  they  are  without  the  substances 
which  have  just  been  named.  The  calcareous  and  magnesian  rocks 
which  are  most  favorable  to  nitrification,  under  the  influence  of  ani- 
mal emanations  and  of  vegetables  in  a  state  of  decomposition,  are 
those  which  are  the  least  coherent,  or  which  are  most  porous,  such 
as  chalk,  tufa,  &c.  In  those  countries  where  the  soil  does  not  un- 
dergo spontaneous  nitrification,  certain  arrangements  of  circum- 
stances, known  to  favor  the  production  of  saltpetre,  are  made  :  arti- 
ficial i\itre-Deds  are  prepared.  In  the  north  of  Europe  where  the 
rocks  are  'granitic,  m  a  hut  or  shed  uuilt  of  wood,  a  mixture  is  made 


250  THEORY  OF  THE  FORMATION  Of  NITRIC  ACID. 

of  common  earth,  of  calcareous  sand  or  marl,  and  of  wood-ashes. 
This  heap  is  watered  with  the  urine  of  herbivorous  animals,  and  the 
mixture  is  stirred  or  shifted  from  time  to  time  to  favor  the  access 
of  the  air ;  and  with  the  same  view,  the  workmen  are  very  careful 
never  to  beat  or  press  the  heap,  which  is  generally  from  two  to  two 
and  a  half  feet  in  thickness,  and  usually  of  the  whole  length  of  the 
hut  or  shed.  Experience  has  shown  that  the  process  of  nitrification 
goes  on  best  in  the  shade.  In  Prussia,  the  practice  is  to  wet  vi'ith 
the  water  of  a  dunghill  a  mixture  composed  of  five  parts  of  vegeta- 
ble earth,  and  one  part  of  wood-ashes  and  straw.  With  this  kind 
of  mortar,  solid  walls  or  masses  from  twenty  to  four  and  twenty 
feet  in  length,  by  about  six  feet  and  a  half  in  thickness,  are  built, 
rods  of  wood  being  introduced  during  the  construction  in  eonsidera- 
ole  numbers,  and  in  such  a  way  that  they  can  be  pulled  out  w^hen 
the  mass  has  acquired  sufficient  solidity  ;  by  this  means  it  is  obvious 
that  a  very  free  access  of  air  is  secured  to  the  interior  of  these 
litre  walls,  which  are  always  built  in  damp  places,  and  thatched  over 
with  straw  to  preserve  them  both  from  the  sun  and  the  rain.  The 
mass  is  watered  from  time  to  time,  and  after  the  lapse  of  a  year, 
'.he  materials  are  held  sufficiently  impregnated  with  saltpetre  to  be 
ivorth  lixiviating. 

In  these  artificial  nitre-beds  we  perceive  the  object  to  be,  to  com- 
)ine  the  circumstances  under  which  the  nitrates  are  formed  in  the 
oil  of  stables,  and  in  the  cellars  of  human  habitations.  Organic 
A  latters,  rich  in  azote,  are,  in  fact,  brought  into  contact  with  earthy 
.  kaline  carbonates.  The  necessity  that  is  felt  in  the  arrangement 
c  *  nitre-beus  for  the  introduction  of  substances  of  animal  origin, 
L  \ds  us  to  presume  that  the  greater  part  of  the  nitric  acid  which  is 
pioduced,  is  derived  from  the  azote  of  these  substances.  But 
whether  tliis  azote  combines  with  the  oxygen  of  the  air,  or  with  the 
oy.ygen  of  the  organic  principles,  we  do  not  know — we  are  still  ig- 
norant of  the  way  in  which  the  acidification  is  effected. 

Professor  Liebig,  setting  out  from  the  fact  that  azotized  organic 
substances  always  produce  ammonia  during  their  putrefaction,  and 
next  perceiving  that  during  the  combustion  of  ammoniacal  gas, 
mixed  with  a  large  excess  of  hydrogen,  there  is  always  oxidation  of 
the  azote,  concludes  that  nitrification  is  the  result  of  the  slow  com- 
bustion of  the  ammonia  which  is  the  product  of  the  azotized  matters 
in  progress  of  decomposition.  The  azote  of  ammonia  is  indeed 
oxidated  under  favor  of  divers  conditions  which  it  is  easy  to  secure. 
In  burning  animal  substances  by  means  of  oxide  of  copper,  it  is  well 
known  how  many  precautions  must  be  taken  to  prevent  the  appear- 
ance of  nitrous  acid  ;  and  on  the  contrary,  by  taking  measures  to 
favor  th.>,  production  of  this  acid,  for  example,  by  passing  a  current 
of  ammoniacal  gas  over  peroxide  of  iron  or  manganese  in  a  red  hot 
tube,  abund.ince  of  nitrate  of  ammonia  is  obtained.  The  same  re- 
sult follows  exposure  of  a  mixture  of  oxygen  and  ammoniacal  gas 
to  the  action  of  incandescent  spongy  platinum.  The  determining 
cause  of  the  acidification  of  the  azote,  which  forms  an  element  of 
the  ammonia,  is  probably  due  to  this,  that  during  the  combustion  two 


DETECTION  OF  NITRATES  IN  THE  SOIL.  251 

bodies  are  formed  which  are  capable  of  combining  immediately  : 
nitric  acid,  on  one  hand,  and  on  the  other  water,  without  which  this 
acid  could  not  exist.  The  phenomenon,  however,  only  takes  place 
in  this  instance  at  a  considerably  elevated  temperature.  At  ordi- 
nary temperatures,  combustion  of  the  elements  of  ammonia  has  not, 
as  far  as  1  know,  yet  been  observed  ;  and  in  a  series  of  experiments 
which  I  undertook,  proceeding  all  the  while  upon  ideas  completely 
in  conformity  with  those  advanced  by  Liebig,  I  did  not  succeed  in 
forming  any  nitrates  by  enclosing  mixtures  of  chalk,  potash,  «&c.,  in 
an  atmosphere  composed  of  oxygen  and  ammoniacal  vapor. 

In  a  communication  made  to  the  Academy  of  Sciences,  M.  Kuhl- 
man  announces  that  he  had  ascertained  the  presence  of  nitrate  of 
ammonia  in  the  products  of  the  putrefaction  of  animal  matter.  If 
this  announcement  be  confirmed,  if  nitric  acid  be  in  reality  one  of 
the  numerous  products  of  the  putrid  fermentation,  the  nitrification  of 
soils  in  contact  w-ith  organic  matters  would  be  readily  explicable. 
I  must  say,  however,  that  I  have  sought  in  vain  for  nitrate  of  ammo- 
nia in  the  product  of  the  putrid  fermentation  of  caseum.  And  after 
all,  we  should  still  be  at  a  loss  to  account  for  the  formation  of  nitre 
in  many  places,  where  it  appears  to  be  produced  in  the  absence  of 
organic  matter,  as  in  the  saltpetre  soils  of  India,  South  America, 
and  Spain.  Dr.  John  Davy,  who  visited  the  nitre  districts  of  Cey- 
lon, and  Proust,  who  long  inhabited  the  Peninsula,  have  given  it  as 
their  opinion  that  the  nitre  appears  in  soils  which  contain  no  vestiges 
of  organic  matter.  The  assertion  of  Proust,  however,  is  open  to 
suspicion,  inasmuch  as  in  his  memoir  he  affirms  that  the  lands  close 
to  those  that  produce  the  nitre  are  extremely  fertile,  so  that  they 
yield  abundant  crops  without  ever  receiving  manure.  But  at  the 
present  day,  it  is  a  law  that  every  fertile  soil  must  contain  or  receive 
dead  organic  matter.  In  Ceylon,  according  to  Davy,  the  caverns, 
the  walls  of  which  become  covered  with  an  efflorescence  of  salt- 
petre with  such  rapidity,  have  a  fertile  and  thickly  wooded  soil  lying 
over  them,  the  percolations  from  which  may  readily  penetrate  their 
interior.  The  observations  which  I  had  an  opporti'  lity  of  making 
upon  the  nitre  soils  near  Latacunga,  were  not  perhaps  of  sufficient 
precision  ;  but  I  think  I  can  affirm  that  the  soil  was  not  without  hu- 
mus :  patches  were  perceived  here  and  there  that  were  covered  with 
turf  It  must  still  be  admitted,  however,  that  in  the  localities  which 
have  been  particularly  indicated  there  must  exist  some  peculiar  and 
permanent  cause  of  nitrification ;  inasmuch  as  in  other  and  fertile 
soils,  saltpetre  only  appears  as  it  were  accidentally,  and  never  in 
extraordinary  quantity. 

Whatever  the  value  of  the  ingenious  but  still  very  imperfect  theo- 
ries of  nitrification,  it  is  still  of  importance  to  ascertain  the  exist- 
ence or  absence  of  nitrates  in  the  soil.  Wollaston  recommended 
a  process  which  enables  us  to  do  this  very  readily.  It  is  founded 
on  the  property  possessed  by  the  aqua  regia — a  mixture  of  the  nitric 
and  hydrochloric  acids — to  dissolve  pure  gold,  which,  as^is  familiarly 
knuwn,  resists  the  action  of  either  of  these  acids  applied  separately. 
The  soil  in  which  the  presence  of  a  nitrate  is  suspected  ie  treated 


252  FARM-YARD    DUNG. 

with  boiling  distilled  water,  and  thrown  upon  a  filter.  The  filtered 
fluid  is  reduced  by  evaporation  to  a  very  small  quantity,  which  is 
then  poured  into  a  test  tube,  and  a  little  pure  hydrochloric  acid  is 
added  ;  some  particles  of  leaf  gold  are  then  introduced,  and  the 
fluid  is  stirred  with  a  glass  rod.  If  any  nitrates  have  been  present, 
the  particles  of  gold  are  speedily  dissolved. 

Having  now  described  the  circumstances  which  determine,  and 
the  phenomena  which  accompany  the  decomposition  of  dead  or- 
ganic matter,  I  have  next  to  treat  of  manures  in  particular,  of  their 
preparation,  of  their  application,  and  of  their  relative  values. 
Speaking  generally,  the  manure  which  is  derived  from  the  dejec- 
tions of  animals,  supplied  in  a  farm-yard  with  abundance  of  food 
and  of  litter,  used  with  the  double  object  of  cleanliness  and  health, 
is  the  best  of  all.  The  principal  substances  which  contribute  day 
by  day  to  increase  the  mass  of  our  dunghills  are  straw,  and  the  ex- 
cretions and  urine  of  horned  cattle,  horses,  hogs,  &c.  These  va- 
rious substances,  besides  the  organic  elements  which  enter  into  their 
composition,  further  contain  the  various  mineral  substances  which 
are  indispensable  to  the  development  of  vegetables.  Animal  excre- 
ments of  every  kind,  in  fact,  when  they  are  burned,  leave  quantities 
of  ashes  which  are  frequently  very  considerable,  and  in  which  are 
encountered  the  same  saline  and  earthy  ingredients  that  pre-existed 
in  the  forage  with  which  the  animals  were  supplied.  Excrements, 
therefore,  necessarily  vary  in  their  composition  according  to  the 
kind  of  food  that  is  consumed,  and  the  nature  and  the  state  of  health 
of  the  animal  which  produced  them.  Those  of  the  herbivora  have 
never  been  sufficiently  examined.  Thaer  and  Einhof  have  merely 
ascertained  that  cow-dung  contains  an  extractive  principle,  partly 
coagulable  by  heat,  and  that  remains  of  the  food  may  be  separated 
from  it.  All  excrementitious  matters,  in  fact,  contain  a  certain 
quantity  of  the  alimentary  matter  which  has  escaped  digestion, 
especially  when  animals  are  abundantly  supplied  with  food.  Some 
albuminous  matter  is  also  found  there  ;  but  the  substance  after  vege- 
table remains  that  appears  to  predominate  is  bilious.* 

We  know  that  after  mastication,  the  food,  mingled  with  saliva  and 
the  secretions  of  the  mucous  glands,  passes  into  the  gullet,  and  from 
thence  into  the  stomach.  There  it  imbibes  gastric  juice,  turns  sour, 
becomes  modified,  and  is  finally  converted  into  a  kind  of  pulp  which 
is  called  chyme.  Once  formed,  chyme  passes  into  the  small  intes- 
tines, where  it  encounters  the  bile  and  pacreatic  juice,  which  modify 
it,  and  cause  it  to  separate  into  chyle,  which  is  absorbed  by  the  ves- 
sels of  the  bowels,  and  excrementitious  residue,  which  descends  into 
the  large  intestines,  where  it  becomes  a  fetid  mass  that  is  expelled 
from  time  to  time  by  the  animal. 

*  The  latest  inquiries  of  the  physiological  chemists  would  lead  us  to  suspect  that 
this  was  not  the  case.  Bile  ought  only  to  be  an  occasional,  and  even  an  unnatural 
constituent  of  animal  excrement,  if  these  views  be  well  founded.  It  seems  that  the 
elements  of  bile  added  to  the  elements  of  starch  supply  the  precise  elements  of  fat  ,•  a 
BUbstnnce  so  abundantly  formed  in  the  process  of  digestion.  The  bile  that  is  poured 
Into  the  upper  part  of  the  uUiucnUry  cauul  is  probjOiiy  all  usod  up  in  forming  Ikt— 
Sack  Ed. 


MANURES — URINE.  258 

The  bile  which  accompanied  the  fecal  matter  is  secreted  by  the 
liver,  and  is  familiarly  known  as  a  viscid,  bitter  fluid  bf  a  yellowish 
green  color  and  a  peculiarly  nauseous  odor.  According  to  M  The- 
nard,  the  bile  of  the  ox  contains  : — 

Water 700 

Picromel*  69 

Fatty  matter 15 

Soda,  phosphate  of  soda,  chlorides  of  potassium  and  > ,« 

sodium,  sulphate  of  soda j  ^" 

Phosphate  of  lime,  oxide  of  iron 1 

Urine  is  a  liquid  secreted  by  the  kidneys  from  arterial  blood  ;  it 
passes  into  the  bladder  by  the  ureters.  Its  composition  varies  ac- 
cording to  the  animals  which  produce  it.  Urea  is  its  most  charac- 
teristic principle  ;  and  in  the  water  which  it  always  contains  in  large 
proportion,  various  saline  substances  and  animal  matter,  which  is  re- 
garded as  mucus  of  the  bladder,  are  encountered.  The  urine  of  the 
horse,  according  to  M.  Chevreul,  contains  carbonate  of  soda,  of  lime, 
and  of  magnesia,  sulphate  of  soda,  chloride  of  sodium,  hippurate  of 
soda,  urea,  and  a  red-colored  oil. 

The  urine  of  horned  cattle  has  a  similar  compositon,  with  this  dif- 
fer ence,  that  it  is  much  more  watery.  In  the  urine  of  our  cow- 
houses which  had  undergone  change,  I  have  ascertained  the  presence 
of  the  alkaline  carbonates,  of  common  salt,  and  of  the  reddish  oil 
mentioned  above.  Having  at  various  times  had  occasion  to  evapor- 
ate considerable  quantities  of  the  urine  of  the  horse,  I  always  ob- 
served that  on  coming  to  the  boiling  point,  a  quantity  of  azotized 
matter  which  resembled  albumen  was  coagulated.  I  also  perceived 
in  the  urine  of  herbivorous  animals  a  volatile  acid,  to  which  its  odor 
is  probably  owing. 

In  the  urine  of  the  camel,  M.  Chevreul  found  the  carbonates  of 
lime  and  magnesia,  silica,  sulphate  of  lime,  and  oxide  of  iron,  in 
very  small  quantities ;  chloride  of  potassium,  carbonate  of  potash, 
sulphate  of  soda,  in  small  quantities  ;*  sulphate  of  potash,  in  large 
quantity ;  urea ;  an  alkaline  hippurate  ;  and  a  reddish  oil. 

The  urine  of  the  rabbit,  according  to  Vauquelin,  contains  carbon- 
ate of  lime,  of  magnesia,  and  of  potash,  chloride  of  potassium,  sul- 
phate of  potash,  sulphur,  urea,  and  mucus. 

The  urine  of  birds  is  distinguished  by  the  large  proportion  of  uric 
acid  it  contains.  Food,  however,  has  a  great  influence  upon  this 
proportion ;  highly  azotized  aliments  increasing  it  considerably. 
Wollaston  observed  that  the  excrements  of  a  fowl  which  was  fed 

*  Picromel,  discovered  in  the  bile  of  the  ox  by  M.  Thenard,  is  colorless,  and  of  the 
consistence  of  sirup.  It  produces  upon  the  tongue  an  acrid  and  bitter  sensation,  which 
rapidly  changes  to  a  flavor  slightly  sugary.  The  recent  researches  of  Messrs.  Tiede- 
mans  and  Gmelin  have  discovered  in  ox  bile  substances  which  had  escaped  the  first  in- 
vestigations. These  chemists  found  :  1st.  a  subst-ince  having  the  smell  of  musk,  and 
which  is  probably  one  of  the  causes  of  the  odor  peculiar  to  the  excrement  of  kine;  2d. 
fatty  substances ;  3d.  biliary  resin :  4th.  a  crystallized  substance  called  taurine :  5th. 
biliary  sugar,  of  wliich  azote  forms  one  of  the  elements.  According  to  Messrs.  Tiedc 
mann  and  Gmelin,  the  picromel  of  M.  Thenard  results  from  the  union  of  sugar  and 
biliary  resin. 


254  MANURES THE  PUTREFACTIVE  FERMENTATIOIf . 

upon  herbage  contained  only  2  per  cent,  of  uric  acid.  That  of  a 
pheasant  fed  upon  barley  contained,  on  the  contrary,  14  per  cent. ; 
and  that  of  a  falcon  which  fed  upon  flesh  alone,  yielded  scarcely  any 
thing  but  uric  acid.  The  urine  of  an  ostrich  was  found  by  Fourcroy 
and  Vauquelin  to  contain  uric  acid  in  the  proportion  of  about  one  six- 
teenth of  its  mass. 

I  have  already  given  the  composition  of  urea.  Hippuric  acid  is 
an  azotized  acid  which  is  readily  obtained  by  adding  a  little  hydro- 
chloric acid  to  the  fresh  urine  of  the  horse  reduced  by  evaporation  to 
about  one  tenth  of  its  original  volume,  when  a  granular  crystalline 
mass  is  precipitated.  If  the  urine  have  been  stale  instead  of  fresh, 
benzoic  acid  and  not  hippuric  acid  is  obtained  ;  benzoic  acid  was,  in 
fact,  long  admitted  as  one  of  the  elements  of  the  urine  of  herbivorous 
animals  ;  but  it  is  derived  from  the  transformation  of  hippuric  acid 
into  benzoic  acid  and  ammonia,  the  change  being  produced  by  con- 
tact with  the  organic  matters  which  putrefy  so  quickly  in  urine. 
Liebig  was  the  author  of  this  observation;  it  was  in  operating  upon 
unchanged  urine  that  he  discovered  hippuric  acid.  The  following  is 
its  composition : — 

Carbon 60.7 

Hydrogen .5.0 

Oxygen 26.3 

Azote   8-0 

100.0 

Uric  acid  has  not  yet  been  met  with  in  the  urine  of  mammiferous 
herbivora  ;  but  it  exists  in  that  of  man,  having  been  first  discovered 
in  calculi  from  the  bladder ;  whence  it  received  the  name  of  lithic 
acid.     Liebig's  analysis  shows  it  to  be  composed  of : — 

Carbon 36.1 

Hydrogen 2.4 

Oxygen 28.2 

Azole 33.4^ 

lOO.O 

The  litter  most  commonly  used  to  absorb  the  urine  of  stall-kept 
animals  is  wheat  straw,  which  consists  in  principal  part  of  lignine 
or  woody  fibre  :  like  all  vegetable  tissues,  however,  it  contains  an 
azotized  principle,  and  substances  that  are  soluble  in  caustic  alkalies. 
In  the  ashes  of  straw,  we  have  indicated  silica  as  abundant,  and  va- 
rious alkaline  and  earthy  salts.  The  proportion  of  azote  appears  to 
vary  in  t|ie  ratio  of  from  3  to  6  per  1000.  An  analysis  which  I  made 
of  dry  wheat  straw  gave  the  following  elements  : — 

Carbon  48.4 

Hyilrogen 5.3 

Oxygen 38.9 

Azote    00.4to0.6 

Ashes 07.0 

100 

Agriculturists  have,  in  all  ages,  admitted  that  the  most  powerfu. 
manures  are  derived  from  animal  substances,  an  opinion  or  rather  a 
fact,  which,  expressed  in  scientific  language,  anounts  to  this,  that 


MANURES LVALUE  OF  AMMONIACAL  SALTS.  255 

rtie  most  active  manures  are  precisely  those  which  contain  the  largest 
proportion  of  azotized  principles.  It  is  obvious  indeed  from  every- 
thing which  precedes,  that  all  the  substances  which  contribute  to 
form  farm  dung,  contain  azote ;  and  that  into  many  of  them,  such  as 
uric  acid,  hippuric  acid,  and  urea,  this  element  enters  very  largely. 

When  we  consider  the  immediate  changes  which  all  highly  azo- 
tized substances  undergo  in  the  process  of  putrefaction,  we  can  fore- 
see that  in  their  transformation  into  manure,  they  must  give  origin 
to  ammoniacal  salts ;  and  well-established  facts  prove  beyond  d.oubt 
that  salts,  having  ammonia  for  their  base,  must  be  ranked  among 
the  most  powerful  of  all  the  agents  in  promoting  vegetation.  It  is 
sufficient,  for  instance,  to  bear  in  mind  that  in  the  productive  hus- 
bandry of  Flanders,  putrid  urine  is  the  manure  that  is  employed  with 
the  greatest  success ;  but  we  have  seen  that  by  putrefaction,  the 
urea  of  the  urine  is  entirely  changed  into  carbonate  of  ammonia. 
The  fields  of  Flanders  are  consequently  fertilized  with  a  solution 
of  carbonate  of  ammonia  in  water. 

Along  a  great  extent  of  the  coast  of  Peru,  the  soil,  which  con- 
sists of  a  quartzy  sand  mixed  with  clay,  and  is  perfectly  barren  of 
itself,  is  rendered  fertile,  is  made  to  yield  abundant  crops,  by  the 
application  of  guano;  and  this  manure,  which  effects  a  change  so 
prompt  and  so  remarkable,  consists  almost  exclusively  of  ammoniacal 
salts.  It  was  with  this  fact  before  me  that  in  1832,  when  I  was  on 
the  coasts  of  the  Southern  Ocean,  I  adopted  the  opinion  which  I 
now  proclaim  in  regard  to  the  utility  of  the  salts  having  a  basis  of 
ammonia  in  the  phenomena  of  vegetation.  I  have  stated  my  views 
on  this  subject  in  a  memoir  published  in  1837.*  Previous  to  this 
publication,  however,  M.  Schattenmann,  one  of  the  most  ingenious 
manufacturers  of  Alsace,  had  already  directed  the  attention  of  hus- 
bandmen to  this  important  matter,  by  reminding  them  that  it  is  the 
custom  in  Switzerland  to  add  sulphate  of  iron  or  green  vitriol  to  the 
urine-vats,  for  the  purpose  of  changing  the  carbonate  of  ammonia 
into  the  sulphate,  and  thus  obtaining  a  fixed  instead  of  a  highly  vola- 
tile salt,  liable  to  escape  and  to  be  lost.  In  a  communication  made 
in  1835  to  the  agricultural  association  of  Bauchsweiler,  M.  Schat- 
tenmann announced  positively  that  the  drainings  from  dunghills 
thus  prepared,  applied  upon  meadow  lands,  produced  very  grea 
effects. 

Such,  to  the  best  of  my  knowledge,  are  the  practical  facts  whicK 
establish  the  useful  influence  of  ammonia  on  the  growth  of  plants 
far  better  than  the  experiments  of  the  laboratory  could  have  done. 
Nevertheless,  it  must  be  acknowledged  that  long  before  the  dates 
above  quoted,  Davy  had  shown  that  water  containing  s^oih  of  car- 
bonate of  ammonia  is  singularly  favorable  to  the  growth  of  wheat, 
far  more  so,  under  circumstances  exactly  similar,  than  the  hydro- 
chlorate  and  the  nitrate  of  the  same  base ;  and  this  influence,  it  is 
important  to  observe,  Davy  ascribed  to  the  fact  that  carbonate  of 
aimnonia  contains  carbon,  hydrogen,  oxygen,  and  azote ;  in  a  wcrd, 

*  Annates  de  Chimie,  t.  Ixv.  2e  sirie,  p.  301. 


256  OTANTTEES — PREPARATION   OF    DtJNG. 

all  the  elements  that  are  essential  to  the  organization  of  plants.  The 
illustrious  English  chemist  concluded  from  his  experiments,  that  the 
well-known  efficacy  of  soot,  as  a  manure,  is  due,  in  part,  to  the  vol- 
atile alkali  which  it  contains. 

Professor  Liebig,  in  adopting  these  opinions,  has  sought  to  gener- 
alize them  ;  he  has  attempted  to  show,  by  very  delicate  experiments, 
that  the  air  which  lies  immediately  over  the  surface  of  the  ground, 
always  contains  carbonate  of  ammonia,  and  that  the  same  salt  can 
be  detected  in  rain  and  snow,  and  in  spring  water.  The  ammonia 
of  the  atmosphere,  according  to  Liebig,  concars  with  that  which  is 
developed  in  manures,  in  the  formation  of  the  azotized  principles 
proper  to  vegetables.  These  ingenious  ideas  correspond  exactly 
with  those  which  M.  de  Saussure  made  public  in  1802,  when  he 
ascertained  that  the  gaseous  azote  of  the  air  is  not  directly  absorbed 
by  plants.  "  If  azote  be  a  simple  substance,  and  not  an  element  of 
water,"  says  this  celebrated  observer,  "  we  must  admit  that  plants 
do  not  assimilate  it,  save  in  vegetable  and  animal  extracts,  and  in 
the  ammoniacal  vapors  or  other  compounds  soluble  in  water  which 
they  absorb  from  the  soil,  or  from  the  atmosphere.  It  is  impossi- 
ble," he  continues,  "  to  doubt  the  presence  of  ammoniacal  vapors  in 
the  atmosphere  when  we  see  that  the  pure  sulphate  of  alumina,  ex- 
posed to  the  air,  ends  by  becoming  changed  into  the  ammoniacal 
sulphate  of  alumina."* 

In  agricultural  establishments,  in  which  the  importance  of  manure 
is  duly  appreciated,  every  precaution  is  taken  both  for  its  production 
and  preservation.  Any  expense  incurred  in  improving  this  vital 
department  of  the  farm,  is  soon  repaid  beyond  all  proportion  to  the 
outlay.  The  industry  and  the  intelligence  possessed  by  the  farmer, 
may  indeed  almost  be  judged  of  at  a  glance  by  the  care  he  bestows 
on  his  dunghill.  It  is  truly  a  deplorable  thing  to  witness  the  neglect 
which  causes  the  vast  loss  and  destruction  of  manure  over  a  great 
part  of  these  countries.  The  dunghill  is  often  arranged  as  if  it  were 
a  matter  of  moment  that  it  should  be  exposed  to  the  water  collected 
from  every  roof  in  the  vicinity,  as  if  the  business  were  to  take  ad- 
vantage of  every  shower  of  rain  to  wash  and  cleanse  it  from  all  it 
contains  that  is  really  valuable.  The  main  secret  of  the  admirable 
and  successful  husbandry  of  French  Flanders  may  perhaps  lie  in 
the  extreme  care  that  is  taken  in  that  country  to  collect  every  thing 
that  can  contribute  to  the  fertility  of  the  soil.  Our  agricultural  so- 
cieties, which  are  now  so  universally  established,  would  confer  one 
of  the  greatest  services  on  the  community  if  they  would  encourage 
by  every  means  at  their  command  economy  of  manure  ;  premiums 
awarded  to  those  farmers  who  should  preserve  their  dunghills  ia 
the  most  rational  and  advantageous  manner,  would  prove  of  more 
real  service  than  premiums  in  many  other  and  more  popular  direc- 
tions. 

The  place  where  the  dung  of  a  farm  is  laid  ought  to  be  rather 
noar  to  the  stables  and  cow-houses.     The  arrangements  may  be 

♦  Becherches  Chimiquos,  p.  207. 


MANURES THE   DUNG-HEAP.  257 

jraried  to  infinity,  but  they  ounrht  all  to  combine  the  following  condi- 
tions :  1st.  That  the  drippings  from  the  heap  should  not  run  away, 
but  should  be  collected  in  a  tank  or  cistern  under  ground  ;  2d.  That 
iio  water,  except  the  rain  which  falls  on  the  dung-heap,  or  any  wa- 
ter that  may  be  thrown  upon  it  on  purpose,  should  be  allowed  to 
drain  into  this  reservoir ;  3d.  That  the  place  for  the  dunghill  be  of 
size  enough  to  avoid  the  necessity  of  heaping  the  manure  to  too 
great  a  height.  The  ground  upon  which  the  dung  is  piled  ought  to 
slope  gently  one  way  or  another — from  each  side  towards  the  centre 
is  best — so  that  the  drippings  may  be  collected  in  the  tank  or  cis- 
tern. It  is  also  desirable  that  the  soil  underneath  should  be  clayey 
and  impermeable  ;  where  it  is  not  so,  it  becomes  necessary  to  pud- 
dle, to  cement,  or  to  pave  the  bottom  of  the  dunghill  stance  as  well 
as  the  bottom  and  sides  of  the  tank  or  cistern.  The  water  which 
runs  from  the  heap  should  be  thrown  back  upon  it  occasionally,  by 
means  of  a  pump  and  hose,  so  as  to  preserve  it  in  a  state  of  constant 
moistness.  The  opening  into  the  tank,  which  is  best  placed  imme- 
diately under  the  centre  of  the  dung-heap,  is  closed  by  means  of  a 
strong  grating  in  wood  or  iron,  the  bars  being  sufficiently  close  to 
prevent  the  solid  matters  from  passing  through.  One  very  impor- 
tant arrangement,  one  which,  in  fact,  must  on  no  account  be  over- 
looked, is  that  the  drains  from  the  stables  and  cow-houses  be  so 
contrived,  that  they  all  run  to  the  dunghill.  The  litter,  however 
abundant,  never  absorbs  the  whole  of  the  urine,  especially  at  the 
time  when  the  cattle  are  upon  green  food  ;  and  it  would  be  quite 
unpardonable  in  the  husbandman  did  he  not  take  measures  to  se- 
cure this,  the  most  valuable  portion  of  the  manure  at  his  disposal. 

The  litter  mixed  with  the  droppings  of  the  animals,  and  soaked 
with  their  urine,  ought  to  be  carried  from  the  stables  to  the  dunghill 
upon  a  light  barrow.  The  practice  of  dragging  out  the  manure  with 
dung-hooks,  which  is  often  permitted  when  the  field  upon  which  it 
is  to  be  spread  is  at  no  great  distance,  ought  on  no  account  to  be  al- 
lowed ;  the  loss  from  the  practice  is  always  considerable. 

Materials  ought  not  to  be  thrown  on  the  dunghill  at  random  or 
hap-hazard ;  they  should  be  evenly  spread  and  divided  ;  an  uneven 
heap  gives  rise  to  vacancies,  which  by  and  by  become  mouldy,  to 
the  great  detriment  of  the  manure.  It  is  of  much  importance  that 
the  heap  be  pretty  solid,  in  order  to  prevent  too  great  a  rise  of  tem- 
perature, and  too  rapid  a  fermentation,  which  are  always  injurious. 
Particular  care  must  also  be  taken  that  the  heap  preserves  a  suffi- 
cient degree  of  moistness,  not  only  of  its  surface  but  of  its  entire 
mass,  which  is  effected  by  watering  it  frequently.  At  Bechelbronn, 
our  dung-heap  is  so  firmly  trodden  down,  in  the  course  of  its  accu- 
mulation, by  the  feet  of  the  workmen,  that  a  loaded  wagon  drawn 
by  four  horses  can  be  taken  across  it  without  very  great  difficulty. 
The  thickness  of  the  heap  is  not  a  matter  of  indifference  :  besides 
the  convenience  of  loading,  which  must  not  be  forgotten,  any  great 
thickness  may  become  injurious  by  causing  the  temperature  to  rise 
too  high  ;  circumstances  occurring  which  should  compel  us  to  keep 
a  mass  in  this  state  for  any  length  of  time,  the  decomposition  would 

22* 


258  PREPARATION  OF   MANURE. 

make  such  progress  as  to  occasion  very  great  loss.  Experience  has 
shown  that  the  thickness  of  a  dung-heap  ought  not  to  exceed  from 
about  four  feet  and  a  half  to  six  feet  and  a  half;  it  ought  certainly 
never  to  exceed  the  latter  amount. 

With  a  vievT  to  prevent  the  drying  of  the  dung-heap  and  its  con- 
sequences, too  great  a  rise  in  temperature  and  destruction  of  manure, 
it  is  the  practice  in  some  places  to  arrange  the  dung-heap  on  the 
north  side  of  a  building,  which  is  undoubtedly  advantageous,  but  not 
always  to  be  realized,  especially  in  connection  with  a  farm  of  some 
magnitude,  where  the  immediate  vicinity  of  a  large  mass  of  matter 
in  a  state  of  putrid  fermentation  is  not  only  unpleasant,  but  may  be 
unwholesome.  In  the  north  of  France,  the  dung-heap  is  sometimes 
shaded  from  the  sun  by  means  of  a  row  of  elms,  and  the  shelter  thus 
secured  is  vastly  preferable  to  that  which  it  has  been  proposed  to 
obtain  by  means  of  a  roof  or  shed,  which,  besides  other  inconveni- 
ences, would  be  found  costly  at  first,  liable  to  speedy  decay,  &c. 
If  circumstances,  such  as  the  smallness  of  the  farm,  the  permeable 
nature  of  the  soil,  &c.,  prevent  the  construction  of  a  reservoir,  there 
is  risk  of  the  dung-water  being  quite  lost;  but  such  waste  may  be 
prevented  by  covering  the  bottom  of  the  pit  or  stance  for  the  dung- 
heap  with  a  bed  of  sand,  peat  marl,  or  any  other  dry  and  porous  sub- 
stance capable  of  absorbing  liquids.  This  practice  is  often  followed 
by  the  farmers  of> Alsace. 

In  some  farms,  the  different  kinds  of  dung  are  piled  apart  from 
one  another  in  particular  heaps  ;  that  of  the  stable  being  put  by  it- 
self, as  well  as  that  of  the  cow-house,  that  of  the  hog-stye,  and  that 
of  the  sheep-pen.  In  great  establishments,  such  a  separation  is 
often  one  of  necessity  ;  but  the  advantages  which  are  ascribed  to  it 
are  questionable  at  least,  and  the  remarks  that  have  been  made  upon 
it  by  writers  do  not  appear  founded  on  any  accurate  observation. 
Without  denying  that  certain  crops  answer  better  when  special  ma- 
nures are  employed,  it  still  seems  to  me  more  advantageous  to  pile 
■»,very  kind  of  manure  together,  when  the  difficiilties  of  the  situation 
are  not  such  as  to  make  this  either  particularly  inconvenient  or  ex- 
pensive. In  this  way,  indeed,  a  dung-heap  of  medium  constitution 
is  obtained,  which  is  regarded  with  reason  as  that,  the  application 
of  which  to  the  soil  is  attended  with  the  greatest  advantages  in  the 
majority  of  instances.  The  distinction  which  seme  have  sought  to 
make  between  the  relative  qualities  of  manures  of  different  origins 
is  far  too  absolute  ;  and  this  is  the  reason,  without  doubt,  wliich 
renders  it  so  difficult  to  bring  the  observations  of  different  agricultu- 
rists to  agree.  Thus,  according  to  Sinclair,  the  dung  of  the  hog- 
stye  is  the  most  active  of  all,  the  richest  in  fertilizing  principles ; 
according  to  Schwertz,  on  the  contrary,  it  is  the  most  indifferent 
manure  of  the  farm-yard. 

The  fact  is,  that  manures,  which  are  the  produce  of  the  same 
animals,  often  present  greater  differences  in  regard  to  quality,  than 
manures  which  proceed  from  diferent  sources  I  shall  show  by 
and  by  that  the  value  of  manure  dfj^ends  especially  upon  the  feeding 
the  age,  and  the  condition  in  which  the  animal  ia  placed  that  pro- 


PREPARATIOTT  OF  MANTJRE.  259 

iTuces  it.  It  is  well  known  that  the  dung  of  cattle,  fed  during  winter 
upon  straw,  is  greatly  inferior  to  that  which  they  yield  when  con- 
suming food  of  a  more  nutritious  quality. 

When  the  litter  mixed  with  animal  excrements  is  accumulated  in 
sufficient  quantity  in  the  pit  or  on  the  dung  stance,  fermentation 
speedily  sets  in,  and  abundance  of  vapor  is  disengaged.  As  car- 
bonate of  ammonia  is  among  the  volatile  products  of  this  decomposi- 
tion, it  is  of  importance  to  hold  it  under  control  ;  this  is  done  by 
keeping  the  heap  in  a  state  of  proper  moistness,  and  in  excluding  as 
much  as  possible  the  access  of  air.  The  daily  addition  of  fresh 
quantities  of  litter  from  the  stables  and  stalls,  contributes  powerfully 
to  impede  the  dispersion  of  the  volatile  elements,  which  it  is  so  im- 
portant to  preserve  in  manure  ;  duly  spread  upon  the  heap,  each  ad- 
dition becomes,  in  fact,  a  fresh  obstacle  to  evaporation  ;  it  forms  a 
covering  which  plays  the  part  of  a  condenser,  at  the  same  time  that 
it  protects  the  inferior  layers  from  the  direct  contact  of  the  air.  So 
long  as  the  dung-heap  is  kept  up  and  attended  to  in  this  way,  the 
fermentation  is  limited  to  the  inferior  layers  of  the  mass.  Thaer 
even  satisfied  himself  that  air  collected  from  the  surface  of  a  dung- 
heap,  undergoing  moderate  fermentation,  does  not  contain  much 
more  carbonic  acid  than  that -which  is  taken  from  the  mass  of  the 
atmosphere.  Neither  does  a  vessel  containing  nitric  acid,  when 
placed  upon  the  fermenting  mass,  produce  those  dense  white  vapors 
which  are  a  certain  indication  of  the  presence  of  ammonia.  The 
slow  decomposition  which  it  is  of  so  much  importance  to  effect,  is 
not  readily  secured  save  in  masses  sufficiently  trodden  down,  and  in 
which  the  litter  of  different  kinds  has  been  spread  as  evenly  as  pos- 
sible. 

It  is  an  important  point  that  the  manure  should  be  carried  out  to 
the  field  before  the  upper  portions  recently  added  begin  to  undergo 
change,  otherwise  the  whole  mass  enters  into  full  fermentation,  and 
the  volatile  elements,  being  no  longer  arrested  by  the  upper  layer, 
escape  and  are  lost.  One  means  of  preventing  this  loss  in  any  case 
(which  however  can  but  rarely  occur)  in  which  there  was  a  neces- 
sity for  suffering  the  mass  to  become  made  through  its  whole  thick- 
ness, would  be  to  cover  it  with  a  layer  of  vegetable  mould,  in  which 
the  volatile  principles  would  be  condensed  ;  the  layer  of  earth  would 
in  fact  thus  be  converted  into  a  most  powerful  manure. 

The  loss  of  carbonate  of  ammonia,  during  the  fermentation  of 
farm-dung,  is  further  prevented  by  the  use  of  certain  salts  which 
have  the  power  of  changing  the  volatile  carbonate  into  a  fixed  salt. 
It  was  with  a  view  of  bringing  a  re-action  of  this  kind  into  play, 
that  M.  Schattenmann,  the  able  director  of  the  manufactories  of 
Bauchsweiler,  proposed  to  add  to  dung-heaps,  in  the  course  of  their 
accumulation  and  preparation,  a  certain  quantity  of  sulphate  of  iron 
or  of  sulphate  of  lime,  either  of  which  is  decomposed  by  the  carbo- 
nate of  ammonia  evolved,  and  a  fixed  ammoniacal  salt  (the  sulphate) 
is  produced.*     The  loss  of  ammonia  from  dung-heaps  in  the  course 

*  Annales  de  Chiniie,  3e  s6rje,  t.  Iv.  d.  118 


260  PREPARATION  OF  MAPnJRE. 

of  regulated  fermentation,  must  not  however  be  estimated  too  hignly  ; 
when  the  decomposition  is  carefully  conducted,  the  mass  having 
^een  well  trodden  and  properly  damped,  the  loss  is  really  very  small. 
The  gentle  fermentation,  secured  by  these  means,  has  characters 
which  differ  essentially  from  those  that  accompany  the  rapid  putre- 
faction which  never  fails  to  take  place  when  matters  are  not  well 
managed.  As  an  example  of  the  rapid  and  injurious  fermentation 
of  which  I  speak,  I  may  cite  that  which  frequently  takes  place  in 
piles  of  horse-dung :  every  one  must  have  seen  such  dung-hills 
loosely  thrown  together,  left  to  themselves,  without  any  addition  of 
water,  acquiring  a  very  intense  heat  in  the  course  of  a  few  days, 
and  have  even  heard  of  their  taking  fire.  I  have  seen  piles  of  this 
kind  reduced  to  their  merely  earthy  constituents!  Such  are  never 
the  results  of  the  moderate  and  gradual  decomposition  which  farm- 
dung  ought  never  to  exceed.  When  the  pit  or  stance  is  emptied, 
in  which  a  slow  and  equal  fermentation  has  taken  place,  the  superior 
layer  is  seen  to  be  very  nearly  in  the  same  state  in  which  it  was 
when  it  was  piled  ;  the  layer  immediately  beneath  this  one  is  chang- 
ed in  a  greater  degree,  and  sometimes  exhales  a  slight  ammoniacal 
odor.  In  the  lower  strata,  the  modification  is  yet  greater  in  degree : 
the  straw  has  lost  its  consistency,  it  is  fibrous  and  breaks  into  pieces 
with  the  greatest  ease  ;  the  mass  is  also  progressively  darker  in 
color  as  we  go  deeper,  and  on  the  ground  it  is  completely  black  ; 
the  smell  which  this  part  of  the  heap  exhales,  is  that  of  sulphuretted 
hydrogen,  and  when  it  is  tested,  sulphate  of  iron  is  discovered  ;  no 
doubt  these  sulphurous  products  are  all  the  consequence  of  the  de- 
composition, under  the  influence  of  the  organic  matter,  of  the  sul 
phates  which  were  contained  in  the  manure.  This  is  the  sign  by 
which  I  know  that  farm-dung  is  duly  prepared  ;  the  presence  of 
sulphurets  and  of  the  hydrosulphate  of  ammonia  will  have  no  ill 
effect  upon  vegetation  ;  for  scarcely  is  the  manure  spread  upon  the 
ground,  than  these  products  are  changed  into  sulphates,  and  then 
the  manure  emits  that  musky  smell  which  is  peculiar  to  it.  Fur- 
ther, there  is  no  doubt  but  that  the  state  in  which  a  carefully  tended 
dung-heap  is  found  in  the  end,  is  due  to  the  circumstances  in  which 
it  has  been  placed  and  kept  during  the  whole  time  of  its  preparation  ; 
its  constituent  elements  would  have  gone  through  a  totally  different 
course  in  the  progress  of  their  modification  had  they  been  left  ex- 
posed to  the  open  air.  To  be  satisfied  of  this,  it  is  enough  to  re- 
mark the  powerful  and  purely  ammoniacal  smell  which  meets  us  in 
a  warm  stable,  especially  during  the  summer  season,  upon  the  ground 
of  which  the  urine  of  the  animals  it  contains  is  left  to  decompose. 

From  what  has  now  been  said,  it  will  be  understood  how  destruc- 
tive to  good  manure  is  the  custom  which  obtains  in  certain  countries 
of  turning  dung-heaps  frequently,  of  airing  them  as  it  were,  in  order 
to  hasten  decomposition.  Treated  in  this  way,  stable  litter,  &c., 
does  in  fact  decompose  much  more  rapidly ;  but  it  does  so,  and  I 
own  that  I  do  not  myself  clearly  perceive  the  object  proposed  by  it, 
%t  the  expense  of  the  quality  ;  for  it  is  very  evident  that  the  volatile 


PREPARATION   OF   MANTJRE.  261 

principles  must  be  dissipated  and  lost  in  the  same  propoition  as  their 
points  of  contact  with  the  air  are  multiplied. 

The  plan  of  collecting  all  the  litter  of  the  farm  into  one  particular 
and  appropriate  place,  is  that  which  is  generally  adopted.  Never- 
theless, there  are  countries  in  which  the  dung  is  left  to  accumulate  in 
the  cattle- stalls,  it  being  merely  covered  with  fresh  straw  every  day. 
The  ground  thus  rises  continually  under  *he  feet  of  the  cattle,  so 
that  it  is  necessary  to  have  moveable  cribs  which  can  also  be  raised 
by  degrees.  This  method  is  so  far  convenient,  that  the  necessity 
for  cleaning  out  the  stable  continually  is  avoided  ;  but  little  is  gain- 
ed in  the  end  in  the  matter  of  labor,  for  the  same  mass  of  manure  has 
still  ultimately  to  be  removed.  The  fermentation  of  the  manure 
would  be  greatly  accelerated  by  the  usual  high  temperature  of  the 
stables,  did  not  the  feet  of  the  cattle  tread  the  mass  very  closely, 
and  this  and  the  daily  addition  of  straw  together  produce  the  same 
effect  as  I  have  indicated  in  treating  of  the  management  of  the  dung- 
heap  out  of  doors  :  it  condenses  vapors  and  volatile  particles,  and 
prevents  evaporation.  The  fact  is,  that  in  stalls  and  stables  in  which 
the  dung  is  allowed  to  accumulate  in  this  way,  we  are  not  sensible 
of  any  very  offensive  odor,  and  the  animals  which  live  in  them  breathe 
without  inconvenience,  it  being  always  understood  that  all  communi- 
cation with  the  exterior  is  not  interrupted,  which  in  fact  it  ought 
never  to  be,  even  in  cases  where  the  stables  and  stalls  are  kept  per- 
fectly clean.  This  method  of  proceeding  becomes  almost  impracti- 
cable when  cattle  are  fed  upon  food  that  is  not  dry,  but  on  the  contrary 
that  is  extremely  watery,  such  as  roots,  green  clover,  &c.  ;  the 
quantity  of  urine  that  is  then  passed  is  so  considerable,  and  the 
excrements  themselves  are  so  copious  and  so  liquid,  that  an  enormous 
quantity  of  straw  would  be  required  to  absorb  the  liquid  parts  ;  in 
spite  of  any  reasonable  addition  of  litter,  indeed,  the  animals  would 
still  be  exposed  to  be  kept  in  the  mire,  which  would  doubtless  become 
a  powerful  cause  of  insalubrity  among  them. 

In  Belgium,  according  to  Schwertz,  manure  is  accumulated  in  the 
stables  by  guarding  against  the  inconveniences  which  the  last  mode 
of  proceeding  generally  implies.  The  cattle  are  placed  upon  a  kind 
of  platform  raised  above  the  pavement  of  the  stable,  and  the  drop- 
pings being  withdrawn  from  under  them,  are  trodden  down  and  allowed 
to  accumulate  upon  the  floor. 

One  inconvenience  attending  the  use  of  straw,  is  that  it  is  frequently 
dear  ;  it  is  also  scarce  in  some  countries.  In  those  parts  of  Swit- 
zerland, for  instance,  where  all  the  available  lands  are  meadows,  they 
are  obliged  to  economize  litter  as  much  as  possible,  so  that  they 
even  wash  it,  and  thus  make  it  serve  repeatedly.  Although  it  would 
be  difficult  to  give  a  reason  for  a  practice  which  has  the  effect  of 
increasing  the  bulk  of  the  manure,  adding  to  the  expense  of  transport, 
and  at  the  same  time  diminishing  its  quality  ;  it  is,  nevertheless,  a 
fact  that  this  mode  of  proceeding  has  been  long  in  use  in  various 
Cantons.  We  probably  only  see  here  another  means  of  securing 
even  the  last  particle  of  the  excrementitious  matters  passed  by  cat- 
tle, the  process  employed  being  in  fact  identical  with  that  us^ed  by 


262  tiQtriD  MAiamK. 

the  chemist  in  his  most  delicate  analyses.  In  Switzerland,  the  urinft 
that  is  passed  by  the  cattle  flows  along  a  gutter  which  communicates 
with  a  large  reservoir  containing  water,  in  which  not  only  are  the  sol- 
id excrements  diffused,  but  in  which  the  litter  is  washed,  this  being 
tlianged  only  twice  a  week.  The  reservoir  is  constructed  under 
the  floor  of  the  cow-house  itself,  in  order  to  be  protected  from  the 
frost.  The  fermentation  of  a  mass  so  diluted  is  scarcely  percepti- 
ble, and,  save  from  leakage,  there  is  no  loss  of  decomposing  animal 
matter.  The  liquid  manure  is  raised  by  means  of  a  pump,  and  car- 
ried to  the  meadow  in  tubs  placed  upon  carls.  In  Switzerland  it  is 
also  the  usage  to  employ  the  urine  of  cattle  separately  as  manure, 
under  the  name  of  pvrin;  to  this  liquid  manure,  a  quantity  of  sul- 
phate of  iron  is  frequently  added  with  the  view  of  bringing  the  volatile 
carbonate  to  the  state  of  the  fixed  sulphate  of  ammonia,  as  I  have 
already  said. 

Liquid  manures  have  their  advantages  and  their  inconveniences. 
We  shall  immediately  discuss  their  value  comparatively  with  that 
of  solid  manures,  and  we  shall  be  led  to  adopt  the  opinion  of  M.  Crud 
in  regard  to  them,  viz.,  that  the  advantages  ascribed  to  them  in  Switz- 
erland are  exaggerated.  Whatever  the  form  under  which  manures 
are  applied,  the  question  has  been  warmly  discussed,  whether  it  be 
to  the  interest  or  disadvantage  of  the  agriculturist  to  employ  them 
before  or  after  they  have  undergone  fermentation  1 

Organic  substances,  however,  are  in  no  condition  to  favor  the 
growth  of  vegetables  until  they  have  undergone  material  changes 
which  modify  their  nature.  One  of  the  results  of  this  change,  as 
we  have  seen,  is  the  development  of  ammoniacal  salts.  Fresh  ma- 
nure, such  as  it  comes  from  the  stable,  introduced  immediately  into 
the  ground,  there  undergoes  precisely  the  same  changes,  and  gives 
rise  to  the  same  producis  as  it  does  when  subjected  to  preparation  in 
a  dung-heap  in  the  manner  already  described  ;  there  is  only  this 
difference,  that  being  scattered  and  mixed  with  a  large  quantity  of 
inert  matter,  the  decomposition  takes  place  much  more  slowly  than 
it  does  in  the  heap.  The  question  which  has  been  so  actively  dis- 
cussed, therefore,  reduces  itself  to  this :  is  it  advantageous  to  have 
the  manure  fermented  in  the  soil  it  is  intended  to  fertilize  1  We 
may  be  allowed  to  express  surprise  that  such  a  question  should  have 
been  raised  in  the  present  day,  and  still  more  that  the  afl!irmative 
answer  should  have  been  disputed  by  agriculturists  of  distinguished 
merit.  Some  have  even  gone  so  far  as  to  maintain  that  fresh  ex- 
crements were  injurioui  to  vegetation.  Proofs  to  the  contrary  are 
readily  obtained  ;  it  is  enough  to  recollect  that  in  the  grazing  and 
folding  of  sheep  and  ki.ie,  the  dung  and  urine  pass  directly  into  the 
ground  of  our  pastures  and  fields,  and  who  shall  say  that  the  land 
is  not  benefited  by  what  it  thus  receives  1  Unquestionably  fresh 
manure  in  excess  proves  injurious  to  vegetables,  but  as  much  inay 
be  said  in  regard  to  the  best-fermented  dungs. 

M.  Gazzeri,  an  Italian  chemist,  has  devoted  himself  with  tr.e 
most  laudable  perseverance  to  inquiries  having  for  thoir  object  tu 
I^OW  that  the  general  custom  of  leaving  manures  to  become  d«- 


VALUE    OP   FRESH    AND    MADE   MANURES.  263 

composed  before  leading  them  out  to  the  field  is  attended  with  a 
considerable  loss  of  fertilizing  principles,  and  that  it  is  therefore 
advantageous  to  use  them  in  the  state  in  which  they  come  from  the 
stable.  To  remove  all  doubts  which  might  yet  be  entertained  upon 
the  effects  of  unfermented  manures,  M.  Gazzeri  showed  that  wheat 
could  be  successfully  grown  in  land  which  had  received  an  extraor- 
dinary dose  of  pigeon's  dung,  which  is  regarded  as  one  of  the  most 
active  of  all  manures;  and  horse  droppings,  taiven  at  the  moment 
they  were  passed,  mixed  with  earth,  in  the  proportion  of  one-fourth 
of  the  whole  bulk,  had  no  injurious  effect  on  the  growth  of  the 
cereals.  To  ascertain  the  amount  of  loss  which  fresh  manures  suf- 
fered from  fermentation,  M.  Gazzeri  placed  certain  quantities,  as- 
certained by  weight,  to  putrefy  under  favorable  circumstances  ;  and 
the  decomposition  completed,  he  weighed  them  again.  In  this  way, 
he  ascertained  that  horse-dung,  in  the  course  of  four  n.onths,  lost 
more  than  the  half  of  the  dry  matter  which  it  contained  before  its 
putrefaction.  Davy,  indeed,  had  already  shown  that  there  is  a  loss 
of  volatile  principles,  during  the  decomposition  of  fresh  manures, 
that  must  be  useful  to  vegetation.  Davy's  experiment  consisted  in 
introducing  manure  into  a  retort,  the  extremity  of  which  communi- 
cated with  the  soil  under  turf,  and  he  found  that  in  the  course  of  a 
few  days  the  grass  which  was  thus  exposed  to  the  emanations  from 
the  retort,  grew  with  particular  luxuriance.  Although  it  appears 
certain,  then,  that  in  conducting  the  preparation  of  manure  in  the 
heap  with  prudence,  the  volatile  and  ammoniacal  principles  which 
appear  in  the  course  of  the  putrefaction  may  be  retained,  it  is  never- 
theless unquestionable  that  the  employment  of  manure  directly  and 
without  previous  fermentation,  would  most  effectually  prevent  the 
loss  of  matters  that  must  be  valuable.  Thaer,  Schwertz,  Mr  Coke, 
and  others,  have  consequently  admitted  the  advantages  of  the  latter 
procedure.  In  agreeing  with  them  completely,  which  I  do,  it  still 
remains  certain  that  on  the  greater  number  of  farms,  dung-heaps 
must  be  formed  as  matter  of  necessity.  Manure  is  only  available  at 
certain  determinate  seasons  of  the  year  ;  it  cannot  be  carried  out 
and  spread  as  it  is  produced.  In  Alsace  it  is  carried  out  to  the  fields 
on  which  it  is  to  be  spread  whenever  circumstances  will  permit,  and 
without  regard  to  its  more  or  less  advanced  state  of  decomposition. 
The  circumstances  which  lead  to  its  being  kept  in  the  pit  for  t\\  o  or 
three  months,  also  lead  to  the  manure  being  half  or  more  than  half 
matured  before  it  is  led  out ;  and  this,  after  all,  is  perhaps  the  best 
state  in  which  it  can  be  put  into  the  ground.  It  is  then  easily  incor- 
porated with  the  soil,  and  its  fertilizing  principles  are  already  in  that 
condition  which  enables  them  to  act,  within  a  limited  time,  with 
greater  energy  than  ihey  would  do  were  the  manure  employed  quite 
fresh.  This  is  the  condition  in  which  our  manures  almost  always 
are  at  Bechelbronn  when  we  carry  them  out :  it  rarely  happens  that 
they  have  been  three  months  on  the  stance  before  their  removal. 
Speediness  of  action  is  a  point  which  is  not  without  importance. 
Fresh  dung  will  always  act  more  slowly  than  that  which  has  reach- 
ed a  certain  point  of  decomposition,  and  the  advantage  which  mostly 


264  VALUE    OP   FRESH   AND    MADE    MANURES. 

accrues  to  the  farmer  in  forcing:  his  crops,  will  often  induce  him  to 
use  manure  that  has  ripened  in  the  pit  or  stance. 

In  warm  and  moist  countries,  as  may  be  conceived,  it  is  almost 
matter  of  indifference  whether  the  dung  be  put  into  the  ground  quite 
fresh,  or  in  a  state  of  decomposition  further  advanced  ;  its  decom- 
position, aided  by  the  heat  of  the  climate,  is  always  effected  rapidly 
enough.  But  it  is  otherwise  in  cold  climates,  where  the  tempera- 
ture which  excites  and  maintains  vegetation  is  often  of  short  dura- 
tion, and  must  at  once  be  taken  advantage  of.  During  a  great  part 
of  the  year,  the  ground  is  so  cold  that  organic  substances  buried  in 
it  are  preserved  with  comparatively  little  change.  Under  such 
climatic  conditions,  there  is  no  doubt  that  manures  in  a  state  of  for- 
wardness are  to  be  preferred.  It  is  probably  from  such  motives 
that  the  extensive  use  of  liquid  manures  in  Switzerland  is  derived, 
the  action  of  these  being,  so  to  speak,  immediate  ;  and  it  is  with 
such  manure  that  in  Flanders  the  cultivation  of  various  plants  that 
are  of  great  value  in  manufacturing  processes,  is  carried  on. 

When  the  fermentation  of  manure  has  been  managed  discreetly, 
and  all  the  precautious  requisite  to  prevent  the  dissipation  of  ammo- 
niacal  salts  and  the  loss  of  soluble  elements  have  been  taken,  there 
is  the  immense  advantage  attending  it,  besides  obtaining  immediate 
action,  that  a  manure  is  produced  of  greater  value  under  a  smaller 
bulk  and  a  less  weight.  The  dung-heap  often  loses  a  third  of  its 
bulk  in  undergoing  fermentation,  a  circumstance  which  occasions  an 
important  saving  in  carriage.  A  like  saving  may  be  effected  with 
reference  to  fresh  manures,  by  drying  them  in  the  sun,  which  I  have 
sometimes  seen  done  ;  they  are  thus  reduced  to  one-third  or  one- 
fourth  of  their  original  weight,  and  when  the  distance  to  which  they 
have  to  be  carried  is  great,  there  may  be  real  advantage  in  proceed- 
ing in  this  way. 

An  objection  of  some  moment  made  to  the  use  of  fresh  dung  to 
corn  lands  is,  that  it  usually  contains  the  seeds  of  weeds  and  the 
eggs  of  insects  which  nothing  but  putrefaction  will  destroy.  This 
objection  of  course  loses  all  its  weight  when  the  land  that  is  ma- 
nured is  to  receive  a  crop  which  admits  of  hoeing ;  and  the  custom 
which  obtains  with  us  at  Bechelbronn  of  using  manure  in  every 
state  of  decomposition  to  the  first  crop  in  the  rotation,  is  a  guaran- 
tee that  fresh  manure  is  really  productive  of  no  inconvenience  in 
practice.  Another  difficulty  pointed  out  by  Thaer,  is  that  of  cover- 
ing in  dung  so  long  and  full  of  straw  as  fresh  stable  or  stall  dung. 
This  objection  disappears  when  the  manure  is  laid  in  furrows  formed 
by  the  plough,  as  is  done  in  Alsace,  by  which  means  the  covering  in 
is  effected  by  a  single  operation. 

If  opinions  are  still  divided  upon  the  question  whether  dung  ought 
to  be  employed  before  or  after  fermentation,  they  are  no  less  so  as  to 
the  mode  of  spreading  it,  and  the  best  periods  for  laying  it  on  the 
land.  It  may  be  imagined  that  the  conclusion  come  to  upon  the  first 
question  necessarily  influences,  the  opinions  held  on  the  second. 
Thoge  who  believe  that  manure  may  be  advantageously  used  in  the 
Btate  in  which  it  comes  from  the  stables,  are  altogether  indifferent  io 


SPREADING    OF    MANURE.  265 

regard  to  the  times  of  carryingr  it  out.  They  take  advantage  of  every 
lehiipe  moment  that  occurs  for  performing  this  necessary  work,  which 
is  no  trifling  advantage  ;  it  is  the  practice  which  we  folh)w  at  Be- 
chelbronn — we  carry  out  our  manure  as  we  find  opportunity.  The 
lands  which  are  to  be  manured  in  the  spring  have  frequently  their 
supply  carried  out  during  winter  when  the  frost  enables  us  to  get 
upon  them.  The  dung  first  shot  down  in  little  heaps,  at  regular 
distances,  is  afterwards  spread  as  equally  as  possible,  frequently 
even  upon  ti.e  snow  ;  and  I  have  never  seen  any  ill  effect  from  the 
practice.  The  custom  which  some  farmers  have  of  keeping  dung  in 
large  heaps  in  the  field,  in  order  that  it  may  be  all  spread  and  work' 
ed  under  at  the  same  time  by  the  plough,  is  certainly  objectionable ; 
the  places  upon  which  these  heaps  have  been  laid  are  evidently  too 
strongly  ifianured ;  no  manure,  save  that  which  is  quite  fresh  and 
very  long  i.i  the  straw,  or  which  it  is  proposed  to  spread  immediate- 
ly in  furrows,  ought  ever  to  be  laid  down  in  large  heaps  upon  the 
field. 

The  method  which  I  have  recommended,  of  leaving  manure  spread 
over  the  surface  of  the  fields  exposed  to  the  weather  for  several 
weeks  or  months,  has  been  severely  criticised.  By  such  exposure, 
it  has  been  said  the  dung  must  lose  its  volatile  elements,  and  the 
rain  must  wash  out  and  carry  off  its  more  soluble  parts.  Influenced 
by  such  fears,  some  farmers  do  not  spread  their  dung  until  the  mo- 
ment of  ploughing  it  in.  Such  diversity  of  opinion  among  practical 
men,  all  personally  interested  in  deriving  the  greatest  possible  amount 
of  advantage  from  the  manure  they  employ,  mi.3t  not  be  thought  of 
lightly  :  when  different  modes  of  procedure  in  agriculture  are  the 
subjects  of  debate,  we  must  not  be  in  too  great  a  hurry  to  come  to 
general  conclusions.  Climate  is  not  without  its  influence  in  the 
question  which  now  engages  us.  In  Alsace,  experience  has  pro- 
nounced in  favor  of  the  practice  followed  ;  but  in  other  countries 
there  may  be  very  good  reasons  for  not  proceeding  in  the  same  way. 
In  Alsace,  where  the  annual  depth  of  rain  amounts  to  26.7  inches, 
no  more  than  4.3  inches  fall  during  the  three  months  of  December, 
January,  and  February.  In  a  district  where  a  larger  quantity  of 
rain  falls  during  the  winter,  the  manure  would  probably  suffer  from 
the  procedure  followed  in  Alsace. 

The  quality  of  the  manure  must  also  be  taken  into  consideration. 
A  dunghill  which  contained  a  large  proportion  of  carbonate  of  am- 
monia, which  exhaled  a  strong  smell  of  volatile  alkali,  would  infal- 
libly lose  in  value  by  any  unnecessary  or  prolonged  exposure  to  the 
ail  ;  but  the  loss  becomes  insignificant  when  the  manure,  by  good 
managemert,  is  brought  to  contain  but  a  small  proportion  of  volatile 
ammoniacal  salts,  as  happens  with  manures  which  have  received 
additions  of  gypsum ;  or  otherwise,  when  the  dung-heap  has  been 
carried  out  fresh,  and  at  a  season  so  cold  that  it  can  be  kept  without 
material  change  until  the  period  arrives  for  spreading  it  over  or 
working  it  into  the  ground.  When  the  rains  are  not  excessive, 
the  soluble  parts  of  manure  spread  upon  the  ground  penetrate  and 
remain  in  its  upper  stratum,  exactly  as  happens  when,  instead  of 

83 


266  ELEMENTARY  COMPOSITION  OF  MANURE. 

being  buried,  it  is  spread  upon  the  herbage  in  full  growth.  The 
plan  of  top-dressing  is  often  of  great  use,  and  is  another  and  a  prac- 
tical proof  of  how  little  detriment  results  from  leaving  manure  ex- 
posed to  atmospherical  vicissitudes.  The  procedure  by  top-dressing 
has  arisen  from  necessity  :  it  was  first  resorted  to  with  the  view  of 
giving  the  land  an  addition  to  the  inadequate  dose  of  manure  which 
it  had  received  before  it  was  sown  ;  but  it  has  been  found  to  answer 
so  well  in  many  districts,  that  it  has  been  continued.  We  have  em- 
ployed it  at  Bechelbronn  upon  various  occasions,  even  to  hoed  crops, 
and  with  decided  advantage,  the  main  one  being,  that  time  was  gained 
for  the  production  of  manure. 

In  the  district  of  Marck,  the  practice  of  top-dressing  lands  sowed 
with  winter  grain,  is  rapidly  gaining  ground;  the  dressing  takes 
place  when  the  blade  is  already  above  ground  ;  and  experience  proves 
that  the  passage  of  the  wagons  over  the  field,  and  the  feet  of  the 
horses  and  the  men,  cause  no  appreciable  mischief;  all  traces  of 
them  very  soon  disappear.  Nevertheless  it  is  decidedly  better  to 
take  advantage  of  a  hard  frost,  when  the  land  will  bear  carts, 
&c.,  for  the  performance  of  the  process.  This  plan,  according  to 
Schwertz,  is  found  to  answer  extremely  well  in  Switzerland,  for 
hemp,  and  indeed  for  almost  every  thing  else.  In  my  opinion,  top- 
dressing  ought  to  be  viewed  as  a  means  of  giving  the  soil,  already 
under  a  crop,  the  manure  which  we  had  been  compelled  to  refuse  it 
at  an  earlier  period.  Still,  Thaer  assures  us,  and  his  authority  is 
always  of  great  weight,  that  he  has  loo  frequently  seen  the  good 
effects  of  top-dressings  to  beans,  peas,  and  leguminous  crops  in  gen- 
eral, not  to  be  satisfied  of  the  general  advantages  of  the  method,  in 
connectiim  with  light  soils  especially,  in  which  the  sowing  may  have 
been  late. 

The  elementary  composition  of  farm-dung  is  a  point  which  is  not 
undeserving  of  consideration.  I  have  made  repeated  analyses  of 
that  of  Bechelbronn,  operating  upon  it  in  a  medium  state  of  decom- 
position. The  animals  which  had  produced  this  dung  were  thirty 
horses,  thirty  oxen,  and  from  ten  to  twenty  hogs.  The  absolute 
quantity  of  moisture  was  ascertained  by  first  drying  in  the  air  a  con- 
siderable weight  of  dung,  and,  after  pounding,  continuing  and  com- 
pleting the  drying  of  a  given  quantity  in  the  oil-bath,  in  vacuo,  at  a 
temperature  of  230°  F. 

The  dung  prepared  in  the  winter  of  the  year — 

1837-8  contained 20.4  >  per  cent,  of 

1838-9 22.2J  dry  matter. 

Prepared  in  summer  of  1839 19.6 

Medium 20.7 

Water 793 

Analysis  yielded  the  following  results : 

Ttmei  •f  preparation.        Carbon.     Hydrogen.    Oxygen.  Aiote  Aihct. 

Winter  of  1837-8           32.4  3.8  25.8  1.7  36.3 

32.5  4.1  26.0  1.7  36.7 

38.7  4.5  28.7  1.7  96.4 

Bprin«ofl838               36.4  4.0  191  2  4  38.1 

1839                400  4.3  27.6  S.  4  25.7 

"         •♦                  34.5  4J  27.6  2JQ  HA 


COMPOSITION  OF  FARM-YARD  DUNG.  267 

On  the  average,  farm-dung  dried  at  238°  contains : 

Carbon 35.8 

Hydrogen 4.2 

Oxygen 25.8 

Azote ; 2.0 

Suits  and  earths 32.2 

100.0 

When  moist,  its  composition  is  represented  by — 

Carbon 7.41 

Hydrogen 0.87 

Oxygen 5.34 

Azoie 0.41 

Salts  and  earths 6.67 

Water 79.30 

100.0 

The  constitution  of  dung-heaps  must  of  necessity  vary  ;  those, 
however,  vvliicii  have  a  common  origin  do  not  seem  to  present  very 
great  differences  in  the  proportion  of  their  elements.  Thus,  horse- 
dung,  in  the  south  of  France,  yielded,  on  analysis,  in  the  dry  state, 
2.4  per  cent,  of  azote.  This  manure  contained  only  61  per  cent,  of 
moisture. 

Did  we  but  know  the  composition  and  the  quantity  of  the  excre- 
tions passed,  in  the  course  of  the  twenty-four  hours,  by  the  various 
animals  which  contribute  to  the  production  of  manure,  we  should  be 
able  to  determine  approximatively  what  the  elements  are  which  have 
been  eliminated  in  the  course  of  the  fermentation.  It  would  be  suf- 
ficient to  compare  the  elementary  matter  in  the  litter,  or  fresh  dung, 
as  it  comes  from  the  stable,  with  that  which  exists  in  the  fermented 
or  prepared  manure.  1  have  data  which  I  think  sufficient  tO"  enable 
me  to  institute  this  comparison.  It  must  always  be, borne  in  mind, 
however,  that  the  analyses  which  I  shall  now^  detail  were  made 
upon  the  excrements  of  a  single  individual  of  each  kind.  It  would 
certainly  have  been  preferable  to  have  had  average  analyses  of 
average  qualities ;  but  the  object  I  had  in  view,  when  I  undertook 
these  experiments,  was  quite  different  from  that  which  I  have  nov; 
before  me. 

EXCRETIONS  OF  THE  HORSE.* 

The  horse  was  fed  upon  hay  and  oats.  The  urine  and  the  excre- 
ments together  contained  76.2  per  cent,  of  moisture.  In  twenty-foui 
hours  the  excretions  weighed — moist,  34.2  lbs. ;  dry,  8.1  lbs. 

Their  composition  was  found  to  be — 

In  the  dry  state.    Moist  ditto. 

Carbon 38.6  9.19 

Hydrogen 5.0  1.20 

Oxygen 36.4  8.66 

Azote 2.7  4.13 

Salts  and  earth 17.3  4.13 

Water "  76.17 

1)0.0  100.0 

•  The  size  of  the  horse  was  rather  below  the  average  usual  size  of  farm  YiaraaB. 


tGS  *,OMPOSITION  OF  FARM-YARD  DUNt 


EXCRETIONS    OF  THE  COW. 


The  cow  was  fed  upon  hay  and  raw  potatoes.  The  urine  and  the 
excrements  together  contained  86.4  of  moisture.  The  weight  of 
the  excretions,  in  twenty-four  hours,  was — moist,  80.5  lbs. ;  dry, 
10.9  lbs. 

Their  composition  by  analysis  was  : 

Dry.  WeU 

Carbon 39-8  5-39 

Hydrogen 4-7  0.64 

Oxyfren 35-5  4.81 

Azote 2.6  0.36 

Sails  and  earth 17.4  2.36 

Water ■    "  86.44 

100.0  100.00 

EXCRETIONS    OF    THE    PIG. 

The  pigs,  upon  which  the  observations  were  made,  were  from  six 
to  eight  months  old.  They  were  fed  upon  steamed  potatoes.  The 
urine  and  the  excrements  lost  by  drying  82  per  cent,  of  moisture. 
The  average  of  the  excretions  yielded  by  one  pig  in  twenty-four 
hours  was  :  moist,  9.1  lbs.  ;  dry,  1.6  lb. 

Composition : 

Dry.  Moirt. 

Carbon 38.7  6.97 

Hydiogen 4-8  0-86 

Oxygen 32-5  5.85 

Azote 3.4  O-Gl 

Salts  and  earth 20-6  87.1 

Water "  82.00 

100.0  100.00 

The  litter  that  is  generally  employed  is  wheat-straw.  This  straw, 
in  the  condition  in  which  it  is  used,  contains  26  per  cent,  of  moist- 
're. 

Its  composition  is : 

Dried.  Undriea.                                        * 

Carbon 48.4  35.8 

Hydiogen 5.3  3.9 

Oxygen 38.9  28.8 

Azote 0.4  00.3 

Salt*- and  earth 7-0  5.2 

Water "  26.0 

100.0  100.0 

At  Bechelbronn  each  horse  receives  daily  as  litter  4.4  lbs.  ;  each 
cow  6.6  lbs.  ;  each  pig  4.1  lbs.  of  straw. 

To  the  stables  and  the  cow-houses  together  are  given  every 
twenty-four  hours  132.0  lbs.  of  straw  for  thirty  horses  ;  198.0  lbs. 
for  thirty  horned  cattle  ;  06.0  lbs.  for  sixteen  pigs;  making  396.0 
lbs.  of  straw,  estimated  when  dry  at  292.6  lbs. 

The  composition  of  the  materials  which  constitute  the  dung  pro- 
duced in  one  day  are  set  forth  in  the  following  table  : 


COMPOSITION    OF    FARM- YARD   DUNG. 


269 


ExcretioiiB  yieWad 
ill  24  hours  by 

Wei-ht 
wlieii  dry. 

Wei-ht 

in  the  wet 

state. 

Elements  of  the  dry  matter. 

Water 

Carb. 

Hydro- 

Oxygen 

Azote. 

Salts  & 
earths. 

tin^  till! 
wet  mailer 

Tliiity  horses 

Thirty  horned  cattle 

Sixteen  pigs 

Straw  used  in  litter 

lbs. 

245.08 

326.36 

26.40 

292.60 

lbs. 

1028.28 

2416.48 

146.74 

396.00 

lbs.      1      IDS. 

94.60  12.32 

130.241  «.i.4U 

10.12    1.32 

41.6815.62 

lbs. 

89.10 

116.16 

8. .58 

113.74 

lbs. 
6.60 
8.58 
0.88 
1.10 

lbs. 

42.46 

56.98 

5.50 

20.46 

lbs. 

783.20 

2089.12 

120.34 

103.40 

The  average  or  mean  composition  of  this  mixture  may  be  taken 
as  follows : 


In  the  dry  state. 

In  the  wet  state. 

Carbon. 

Hydrog.   Oxygen. 

Azote. 

Salts. 

Carbbn. 

Hydrog. 

Oxygen. 

Azote. 

Salt. 

Water. 

42.3 

5.0     1     36.7 

1.9 

14.1 

9.4 

1.2 

8.2 

0.4 

3.2 

77.6 

That  of  the  resulting  Bung : 
1               1               1                 1                 1                 1 

35.8 

4.2 

25.8 

2.0 

32.2 

7.4 

0.9 

5.3 

0.4 

6.7 

79.3 

On  comparing  the  composition  of  the  dung-heap  with  that  of  the 
different  kinds  of  litter  collected  in  a  day,  little  difference  is  ob- 
served ;  the  larger  quantity  of  saline  and  earthy  matters  discovered 
in  the  fermented  manure  is  readily  explained  from  the  additions  of 
ashes  incorporated  with  it,  and  also  by  the  accidental  admixture  of 
earthy  matters  proceeding  from  the  sweepings  of  the  court,  the 
earth  adhering  to  the  roots  consumed  as  food,  &c. — refuse  of  every 
kind,  the  residue  after  cleansing  the  various  kinds  of  fodder  for  the 
stable  and  stall,  &c.,  all  goes  to  the  dung-heap.  Lastly,  and  with 
reference  to  the  elements  that  are  liable  to  be  dissipated  in  the  state 
of  gas,  or  which'may  be  changed  into  water,  the  azote  is  percepti- 
bly in  larger  quantity  in  the  prepared  manure  than  in  the  unfer- 
mented  litter  and  excretions.  This  is  at  once  seen  on  comparing 
the  composition  of  these  two  products  after  the  saline  and  earthy 
matters  have  been  deducted. 


The  composition  of  fresh  litter,  is. 
That  of  dung 


Carbon.    Hydrogen. 
.49.3  5.8 

..52.8  6.1 


Oxygen. 
42.7 
33.1 


Azote. 

2 

3.0 


Dung  is,  therefore,  somewhat  richer  in  carbon  than  litter,  and  it 
contains  less  oxygen.  It  is  the  property  of  lignine  undergoing  de- 
composition, that  it  yields  a  product  which  relatively  abounds  more 
in  carbon  than  the  original  matter,  in  spite  of  the  carbonic  acid 
which  is  formed  and  thrown  off  during  the  alterations  undergone  ; 
this  is  owing  to  the  elements  of  water  being  thrown  off  in  relatively 
still  larger  quantity  at  the  same  time. 

Fermented  dung  contains  less  oxygen  than  that  which  comes 
from  tb^  stable;  it  ought  also  to  contain  less  hydrogen:  but  this 
analysis  does  not  proclaim.     It  must  be  observed,  however,  that  the 

23* 


270  DURABILITY    OF   MANURES. 

quantity  of  oxygen  (4.6,)  the  loss  of  which  appears  would  require 
no  more  than  0.57  of  hydrogen  to  constitute  water ;  and  this  is  a 
quantity  which  jt  is  impossible  to  answer  for  in  experiments  made 
upon  such  substances  without  excessive  delicacy  of  tnanipulation. 
This  much  may  be  certainly  concluded,  viz..  that  manure  which  has 
undergone  preparation  contains  a  larger  relative  proportion  of  azote 
than  the  substances  which  have  concurred  in  its  production  ;  and  for 
this  reason,  it  is  very  probable  that  upon  the  whole  a  very  trifling 
loss  of  this  element  is  experienced  if  the  fermentation  has  heen 
carefully  managed,  and  the  manure  has  been  carried  out  and  dis- 
tributed upon  the  land  before  its  decomposition  is  loo  far  advanced. 
This  conclusion,  which  I  am  particularly  anxious  to  establish,  is 
partly  explained  by  the  interesting  researches  of  Mr.  Hermann, 
which  go  to  prove  that  woody  fibre  in  rotting  attracts  and  fixes  a 
quantity  of  the  atmospheric  air. 

Azote  is  in  fact  the  element  which  it  is  of  highest  importance  to 
augment  and  to  preserve  in  dung.  The  organic  substances  which 
are  the  most  advantageous  in  producing  manures  are  precisely  those 
which  give  origin  by  their  decomposition  to  the  largest  proportion 
of  azotized  matters  soluble  or  volatile.  I  say  by  their  decomposi- 
tion, because  the  mere  presence  of  azote  in  matters  of  organic  ori- 
gin does  not  suffice  to  constitute  them  manure.  Coal,  for  example, 
contains  azote  in  very  appreciable  quantity  ;  and  yet  its  ameliorating 
influence  upon  the  soil  is  absolutely  null ;  this  happens  from  coal 
resisting  the  action  of  those  atmospheric  agencies  which  determine 
that  putrid  fermentation,  the  ultimate  result  of  which  is  always  the 
production  of  ammoniacal  salts,  or  other  azotized  compounds  favor- 
able to  the  growth  of  vegetables.  While  we  admit  the  high  impor- 
tance, indeed  the  absolute  necessity  of  azotic  principles  in  manures, 
then,  we  must  not  therefore  conclude  that  these  principles  are  the 
only  ones  which  contribute  to  fertilize  the  earth. 

It  is  unquestionable  that  the  alkaline  and  earthy  salts  are  further 
indispensable  to  the  accomplishment  of  the  phenomena  of  vegeta- 
tion ;  and  it  is  far  from  being  sufficiently  shown  that  the  organic 
principles  void  of  azote  play  a.  merely  passive  part  when  added  to 
the  soil.  But  with  few  exceptions,  the  lixed  salts,  water  or  its  ele- 
ments, and  carbon  superabound  in  manure.  The  element  which 
exists  there  in  smallest  proportion  is  azote,  which  is  the  one  also  that 
is  most  apt  to  be  dissipated  during  the  alteration  of  the  bodies  that 
contain  it.  For  these  reasons  azote  is  really  the  element  whose 
presence  it  is  of  highest  moment  to  ascertain  ;  its  proportion  is  that 
in  fact  which  fixes  the  comparative  value  of  different  manures. 

Since  it  is  by  undergoing  modification  in  the  course  of  their  de- 
composition by  putrefaction  that  those  azotized  substances  which  are 
favorable  to  vegetation  are  developed  in  quaternary  compounds,  it 
will  be  readily  understood  that  all  things  else  being  equal,  a  manure 
which  is  completely  decompoundable  into  soluble  or  gaseous  products 
in  the  course  of  a  single  season,  will  exert  in  virtue  of  this  alone 
the  whoie  of  its  uselul  influence  upon  the  first  crop.  It  is  entirely 
dififereot  if  the  manure  decomposes  more  slowly  ;  its  actioa  upon  ti'O 


STRAW,  STEMS,  ETC.  :271 

first  crop  will  be  less  obvious,  but  its  influence  will  continue  lonjrer. 
There  are  manures  which  act,  it  may  be  said,  at  the  moment  they 
are  put  into  the  ground  ;  there  are  others,  the  action  of  which  con- 
tinues during  several  years.  Nevertheless  two  manures,  although 
acting  within  periods  so  different  in  point  of  extent,  will  produce 
the  same  final  result  if  they  severally  contain  the  same  dose  of 
azotic  elements,  if  they  are  of  the  same  intrinsic  value. 

The  durability  of  manures,  the  length  :f  time  during  which  they 
will  continue  to  exert  their  influence,  is  a  matter  of  great  impor- 
tance. It  often  depends  on  their  state  of  cohesion,  or  on  their  in- 
solubility, though  climate  and  the  nature  of  the  soil  have  also  a 
marked  influence  on  their  decomposition  and  consequent  effects.  It 
}s  not  easy  in  the  present  state  of  knowledge  to  predict  with  cer- 
tainty how  long  the  beneficial  effects  of  a  given  manure  will  con- 
tinue to  be  felt ;  but  we  know  well  enough  what  will  hasten  the 
decomposition  of  manure,  and  what  will  retard  this  final  result,  and 
so  apportion  as  it  were  the  fertilizing  principles  among  the  different 
crops  in  the  rotation.  xA.ware  of  the  importance  of  azote  in  manures, 
M.  Pay  en  and  I  undertook  an  extensive  series  of  analyses,  with  a 
view  to  ascertain  the  proportion  of  this  principle  in  the  various  mat- 
ters and  mixtures  made  use  of  in  the  improvement  of  the  soil.  This 
labor  enabled  us  to  class  manures  ;  and  assuming  farm-dung  as  the 
standard,  to  refer  each  to  its  place  in  a  comparative  scale,  I  shall 
give  the  conclusions  to  which  we  came  in  the  tabular  form  ;  but  be- 
fore doing  this,  I  think  it  necessary  to  premise  a  few  observations 
upon  the  several  manures,  or  substances  usually  employed  in  prepar- 
ing manures. 

Straw,  looody  stems,  haum,  leaves,  and  weeds.  The  straw^  of 
corn,  the  haum  and  stalks  of  various  plants  of  farm  growth,  weeds  of 
allv  kinds,  and  leaves  collected  in  the  woods,  all  contribute  to  in- 
crease the  supply  of  manure. 

Slraio  is  the  article  that  is  generally  employed  for  litter  ;  its  hol- 
low tubular  structure,  which  makes  it  apt  to  imbibe  urine,  renders  it 
peculiarly  valuable  for  this  purpose  ;  and  it  at  the  same  time  sup- 
plies a  soft  and  warm  bed  for  the  cattle.  The  weight  of  the  straw 
used  as  litter  may  be  doubled  by  the  absorption  of  urine  and  admix- 
ture with  excrements  ;  but  it  is  by  its  very  nature  and  of  itself  a 
manure  which  is  not  to  be  slighted,  since  it  contains  from  2  to  6 
thousandths  of  azote. 

The  stems  of  leguminous  plants — bean  and  pea  straw— are  much 
more  highly  azotiz'ed  than  the  straw  of  corn  ;  it  is  certainly  best  to 
consume  this  article  as  forage  when  it  is  not  too  woody  and  hard. 
As  litter  it  is  often  unfit  to  form  a  good  bed  for  cattle,  and  should 
therefore  not  be  so  employed  alone  ;  but  it  presents  the  t\yofold  ad- 
vantage of  adding  to  the  manure  a  large  proportion  of  azotized  prin- 
ciplesTand  at  the  same  time  of  effecting  a  saving  of  straw.  At 
Bechelbronn  we  have  found  it  very  advantageous  to  mix  a  certain 
quantity  of  the  dried  stems  of  the  Madia  saiiva  (gold  of  pleasure) 
\»ith  both  our  cowhouse  and  stable  litter. 

In  fttrest  districts,  the  leaves  of  trees  are  frequently  used  aa  lit- 


1872  LEAVES ^BEAN-STRAW. 

ter  ;  they  perhaps  absorb  urine  in  smaller  quantities  than  straw  iloe». 
but  as  they  are  much  more  highly  azotized,  they  greatly  improve  the 
quality  of  the  dung.  It  is  desirable  that  the  materials  used  for  litter 
should  be  capable  of  imbibing  a  large  quantity  of  liquid  ;  and  these 
same  materials  are  by  so  much  the  more  advantageous  as  the  pro- 
portion of  azote  which  enters  into  their  composition  is  high.  The 
leaves  of  trees  combine  both  of  these  conditions,  and  are  therefore 
an  immense  resource  in  districts  where  they  can  be  procured  in 
abundance.  Where  the  woods  are  strictly  preserved,  the  removal 
of  the  leaves  is  generally  prohibited  ;  and  it  is  doubtless  injurious 
to  deprive  the  soil  of  them  in  young  plantations  ;  but  where  the  tim- 
ber is  further  advanced,  the  objections  to  their  remi>val  are  infinitely 
less,  and  it  is  therefore  generally  permitted  to  carry  them  away 
within  certain  limits.  And  when  it  is  seen  that  from  natural  causes 
a  great  part  of  the  leaves  is  actually  lost  to  the  soil  of  the  forest, 
the  wind  sweeping  them  into  the  ravines,  whence  they  are  carried 
away  by  the  rains,  it  is  evidently  far  better  to  allow  the  poorer  cul- 
tivators to  profit  by  them.  The  benefit  obtained  appears  the  greater, 
as  the  time  and  labor  bestowed  in  collecting  the  leaves  is  not  taken 
into  the  reckoning. 

Bean  straw,  and  other  stalks  of  a  very  hard  and  thready  nature, 
make  but  indifferent  litter,  they  are  often  so  hard  that  they  hurt  cat- 
tle :  and  then  their  cuticle  being  impermeable,  they  absorb  little  or  no 
urine.  It  has  been  proposed  to  crush  them  in  the  mill  or  to  cut  them 
in  pieces,  but  either  of  these  processes  is  attended  with  expense. 
The  best  thing  to  do  would  sometimes  be  to  place  them  where  they 
would  get  crushed  under  the  wheels  of  the  farm  carts.  The  use  of 
woody  stems  of  every  description  would  be  attended  with  unques- 
tionable saving  in  the  useful  article  of  straw,  and  it  must  never  be 
forgotten  that  to  economize  straw  as  litter,  is  to  increase  the  quan- 
tity of  available  forage.  If,  for  example,  it  were  possible  to  reduce 
to  the  state  of  litter  the  woody  stems  of  the  Jerusalem  artichoke  in 
places  where  this  vegetable  is  grown  to  any  extent,  the  advantages 
would  be  very  decided  ;  the  quantity  of  these  stalks  collected  from 
an  acre  may  amount  to  from  four  to  five  tons  ;  the  pith  of  which 
they  are  almost  entirely  composed  is  of  a  very  spongy  nature  and 
well  fitted  to  absorb  fluids.  These  stalks  are  light,  and  properly 
bruised,  would  probably  replace  an  equal  weight  of  straw,  first  as 
litter  and  then  as  an  element  of  the  dunghill,  instead  of  being  burn- 
ed as  at  present  to  heat  the  oven  or  to  boil  the  copper,  which  seerns 
of  all  methods  the  worst  to  derive  any  advantage  from  the  woody 
haum,  whether  of  the  Jerusalem  artichoke,  the  potato,  rape,  &c. 
These  substances  contain  about  4  per  1000  of  azote,  and  are  most 
profitably  transformed  into  manure.  We  have  found  that  by  placing 
them  at  the  bottom  of  the  dung-heaps,  they  end  by  undergoing  de- 
composition ;  even  the  most  woody  stems  of  vegetables,  indeed,  de- 
compose pretty  rapidly  when  ihey  are  impregnated  with  urine  and 
mixed  with  the  droppings  of  animals.  Mere  moisture  without  other 
addition  does  not  suffice,  they  then  rot  with  extreme  slowness. 

The  green  parts  of  vegetables  buried  in  the  ground  with  the  wa- 


GREEN    MANURES.  273 

ler  they  contain,  undergo  decomposition  rapidly  ;  the  best  plan  of 
using  them  as  manure  would  therefore  be  to  plough  them  in  at  once, 
were  there  not  certain  objections  to  this.  In  the  first  place  it  cannot 
always  be  done,  on  account  of  the  season  and  the  crops  upon  the 
ground  ;  and  then  it  might  be  imprudent  to  return  to  the  earth  the 
noxious  weeds  which  had  just  been  pulled  up,  frequently  full  o/ 
seeds,  which  would  not  fail  to  make  their  existence  known  before 
long.  It  is  besides  often  impossible  to  bring  loads  of  weeds  to  the 
farmstead  ;  the  best  thing  that  can  then  be  dont,  is  to  change  them 
rapidly  into  manure  in  a  corner  of  one  of  the  fields  which  has  pro- 
duced them.  This  is  readily  accomplished  by  means  of  lime  ;  a 
bed  is  first  made  of  the  weeds  about  14  inches  thick,  this  is  ther» 
covered  with  a  thin  layer  of  quick-lime,  from  half  an  inch  to  an  inch 
in  thickness ;  another  layer  of  weeds  is  laid  on,  and  then  another 
layer  of  quick-lime,  and  so  on  in  succession.  After  a  few  hours  the 
action  between  the  dry  lime  and  the  moist  herbage  begins,  and  it 
may  be  so  intense  as  even  to  go  the  length  of  burning,  to  prevent 
which  the  pile  must  be  covered  with  earth  or  with  turf,  and  every 
means  used  to  prevent  the  access  of  air.  The  process  is  generally 
complete  within  twenty-four  hours,  and  the  heap  may  then  be  spread 
as  manure.  Before  proceeding  to  such  an  operation,  however,  it 
wouM  be  highly  proper  to  calculate  its  cost.  All  depends  on  the 
price  of  the  lime  and  the  labor ;  and  all  things  considered,  I  myself 
much  doubt  whether  the  plan  could  be  followed  with  advantage. 

Green  manures.  Under  this  title  I  include  the  green  parts  of 
vegetables  which  form  part  of  our  crops,  such  as  the  haum  of  po- 
tatoes, the  outer  leaves  of  carrots,  cabbages,  beet,  turnips,  &c. 
These  articles  are  at  once  forage  and  manure,  and  it  is  for  the  hus- 
bandman to  decide  in  conformity  with  his  position  and  particular 
resources  whether  he  ought  to  bury  them  at  once,  or  to  use  them 
first  as  food  for  cattle. 

From  my  own  experience  I  should  say  that  the  leaves  of  beet 
and  of  turnips,  and  potato  haum  were  articles  which  ought  only  to 
be  given  to  cattle  in  cases  of  necessity.  It  is  generally  much  better 
to  bury  them  in  the  ground  immediately  after  the  crop  is  gathered  ; 
if  they  be  very  indifferent  food,  they  are  on  the  contrary  excellent 
manure,  superior  in  quality  even  to  the  best  farm  dung.  From  the 
experiments  I  have  made  on  this  subject,  I  find  that  the  potato  tops 
from  an  acre  of  ground  may  be  equal  to  6  or  7  hundred  weight  of 
that  manure  presumed  to  be  dry  ;  and  the  leaves  of  the  beet,  from 
the  same  extent  of  surface,  are  equal  to  more  than  21  hundred 
weight  of  the  same  manure,  also  in  a  state  of  dryness.  It  is  among 
green  manures  that  we  are  to  class  the  sea-weed  or  marine  plants, 
which  in  many  places  are  employed  for  improving  the  soil.  These 
cryptogamic  plants,  which  abound  in  azote,  have  a^fertilizing  power 
superior  to  that  of  common  dung,  a  fact  which  explains  the  great 
store  which  is  set  in  Brittany  by  the  sea-weed  that  is  collected  on 
its  coasts.  Sea-weed  is  employed  either  fresh  and  as  it  comes  from 
the  sea,  or  half  dried  or  macerated,  or  roasted,  and  even  partially 
Uiraed.     It  appears  to  act  at  once  in  virtue  of  the  azoiizcd  or 


874  GEEEN    MANURES — SEA-WEED. 

ganic  matters  which  it  contains,  of  the  hygrometric  propert'cs  which 
it  possesses,  and  of  the  saline  substances  which  enter  into  its  com. 
position.  The  agriculturists  of  Brittany  have  employed  sea-weed 
as  manure  from  time  immemorial  ;  and  so  have  the  people  oi 
Scotland  and  Ireland.  In  Brittany,  the  sea-weed  is  gathered  at 
periods  fixed  by  law.  The  first  gathering,  as  well  as  that  which 
has  been  cast  up  by  the  waves,  is  given  up  to  the  poor.  The  gath- 
erings then  take  place  at  regular  intervals  by  means  of  a  kind,  of 
cutting  rake.  The  sea-weed  cut  from  the  rocks  is  piled  upon  rafts 
or  thrown  into  barges,  and  carried  to  the  shore  ;  and  there  is  a  tiade 
carried  on  in  the  article  all  along  the  shores  of  the  channel  between 
Genest  and  Cape  La  Hogue,  from  the  Chansey  Isles,  and  from  the 
coast  of  Calrados. 

When  sea-weed  is  employed  in  the  fresh  state,  it  is  ploughed  in 
as  speedily  as  possible.  For  those  kinds  of  crops  which  require  made 
manures,  the  sea-weed  is  stratified  with  dung  and  so  left  to  ferment. 
In  some  places  the  sea-weed  is  roasted  or  imperfectly  burned,  by 
which,  while  a  large  proportion  of  the  vegetable  tissue  is  destroyed, 
an  azotized  product  is  still  left  behind.  Before  burning  the  sea- 
weed, it  is  exposed  for  a  time  to  the  air  and  the  rain,  and  it  is  then 
dried,  being  frequently  turned.  In  this  state,  it  is  even  used  as  fuel 
in  places  where  wood  is  scarce.  One  great  advantage  in  sea-weed 
which  has  been  particularly  indicated,  is  its  total  freedom  from  the 
seeds  of  noxious  weeds. 

Aquatic  plants  which  grow  in  fresh  water  may  also  be  employed 
as  manure ;  the  common  reed  cut  and  buried  green,  decomposes 
rapidly.  And  here  I  may  mention  that  to  destroy  reeds  which  are 
often  a  cause  of  great  annoyance  in  ponds,  Schwertz  recommends 
lowering  the  water  about  16  inches,  cutting  the  plant,  and  then  rais- 
ing the  water  to  its  old  level ;  the  water  enters  the  interior  of  the 
Mems  and  they  all  die  in  a  very  short  space  of  time. 

Crops  which  are  buried  green,  for  the  improvement  of  the  soil, 
are  also  to  be  ranked  in  the  list  of  the  manures  which  now  engage 
lis.  The  plan  of  burying  green  crops  dates  from  the  most  remote  an- 
tiquity ;  it  was  greatly  recommended  by  the  Romans,  and  is  followed 
in  Italy  at  the  present  day.  The  plants  usually  grown  for  the  pur- 
pose of  being  buried  green  are  colza  or  colewort,  rape,  buckwheat, 
tares,  trefoil,  &c.  The  preference,  however,  is  given  to  one  or 
other  of  the  leguminous  plants,  such  as  tares,  lupins,  &c.,  plants 
which  appear  to  have  the  highest  power  of  extracting  azotized  prin- 
ciples from  the  atmosphere  ;  and  indeed  the  value  of  the  whole  pro 
cess  is  founded  upon  this  fact,  for  otherwise  it  would  be  impossible 
to  give  any  reason  for  this  long  accredited  mode  of  improving  the 
soil.  This,  too,  is  one  of  the  ways  in  which  fallowing  becomes  use- 
ful ;  it  is  not  merely  the  rest  which  the  land  thus  obtains,  it  is  also 
benefited  by  the  vegetables  which  grow  upon  it  spontaneously,  which 
come  to  maturity  and  die,  leaving  in  this  way  in  the  ground  all  they 
had  attracted  from  the  atmosphere,  or  fixed  from  the  water  with 
which  they  had  been  supplied. 

SeedSf  Oil-cake.     It  is  in  the  seed  that  by  fw  the  largest  proper 


OIL-CAKE  MANURE.  275 

tion  of  the  ar.otized  matter  assimilated  by  vegetables  during  theit 
growth  is  finally  concentrated  at  the  period  of  their  maturity.  Seeds 
are  consequently  very  p(»werful  manures,  and  great  advantage  is 
taken  of  them.  In  Tuscany,  lupin  seed  is  sold  as  manure;  it  con- 
tains 3^  per  cent,  of  azote.  It  is  employed  after  its  germinating 
power  has  been  destroyed  by  boiling  or  roasting.  The  cultivation 
of  the  lupin  is  carried  on  in  districts,  the  situation  of  which  is  such 
that  difficulty  would  be  experienced  in  exporting  more  bulky  crops. 
Grains  from  the  brewery  would  also  make  excellent  manure  Were  it 
not  generally  found  more  advantageous  to  use  them  as  food  for  cat- 
tle. In  some  places,  however,  where  there  is  no  adequate  demand 
for  them  in  this  direction,  they  are  dried  upon  a  kiln,  and  are  then 
equal  to  twice  and  a  half  their  weight  of  farm  dung;  in  some  places 
they  are  actually  sold  at  a  proportionate  price.  The  state  if  divis- 
ion of  grains  admits  of  their  being  regularly  spread.  In  some  parts 
of  England,  grains  are  used  in  the  proportion  of  from  40  to  50 
bushels  per  acre  for  wheat  or  barley.* 

The  refuse  of  the  grape  in  wine  countries  contains  a  large  quantity 
of  azotized  matter.  The  decomposition  of  the  grape  stones  being 
slow,  this  refuse  answers  admirably  as  a  manure  for  vines. 

Oleaginous  seeds  after  the  extraction  of  the  oil  leave  a  residue 
which  is  an  article  of  commerce,  and  is  familiarly  known  under  the 
name  of  cake.  Oil  contains  no  appreciable  quantity  of  azote ;  this 
principle  is  contained  entirely  in  the  cake,  which  becomes  through 
this  alone  most  excellent  manure.  The  proportion  of  azote  which 
cake  contains,  varies  from  3|  to  9  per  cent.  Oil-cake,  from  its  mode 
of  preparation,  contains  but  very  little  moisture,  and  consequently  of- 
fers great  facilities  in  the  way  of  carriage  ;  it  may  be  taken  without 
difficulty  to  situations  whither  a  load  of  dung  could  scarcely  be  carried. 

Cake  is  applied  in  two  modes :  1st.  In  powder,  and  by  sowing 
upon  the  field,  sometimes  mixed  with  the  seed.  2d.  Mixed  in  water 
or  in  the  drainings  of  the  dung-hill,  in  which  case  the  liquid  contain- 
ing the  products  of  the  decomposition  of  the  cake  is  distributed  over 
the  land.  By  putrefaction  under  water,  cake  yields  a  matter  of  ex- 
treme fetor,  comparable  both  in  point  of  smell  and  of  effects  on  vege- 
tation to  human  excrement  obtained  from  privies. 

Although  cake,  from  the  large  proportion  of  albumen  and  legumen 
which  it  contains,  be  an  excellent  food  for  cattle,  it  is  still  found 
more  advantageous  in  many  districts  to  use  it  as  manure  than  for 
feeding.  England  imports  oil-cake  from  all  parts  of  the  continent. 
France  alone,  from  1836  to  1840,  exported  more  than  117,860  tons 
of  the  article.  Oil-cake  has  been  particularly  recommended  as 
manure  for  light  sandy  soils.  When  the  soil  is  clayey  and  cold, 
Schwertz  recommends  a  mixture  of  one  part  of  lime  and  6  parts  of 
powdered  cake.  To  me,  however,  the  addition  of  lime  has  always 
appeared  a  questionable  auxiliary  in  such  manures  as  give  rise  readily 
to  ammoniacal  products,  as  is  the  case  with  oil-cake.  For  clayey 
lands,  it  would  perhaps  be  advisable  to  employ  oil-cake  in  a  statn  of 

**  Sinclair,  Agricniture^  vol.  i. 


B76  REFUSE  OF  BEET  AS  XTANURE. 

decomposition  and  diffused  in  water ;  its  effects,  I  imagine,  would 
not  he  doubtful. 

Oil-cake,  as  a  mar.ure,  is  employed  at  very  different  seasons,  ac- 
cording to  the  nature  of  the  husbandry.  It  is  always  well  to  employ- 
it  in  rainy  weather.  Its  effect  is  always  certain,  if  it  comes  on  to 
rain  two  or  three  weeks  after  it  has  been  put  into  the  ground. 
Drought  suspends  its  action ;  it  frequently  happens,  indeed,  that  the 
first  crop  shows  none  of  its  good  effects ;  but  these  never  fail  to  ap- 
pear in  subsequent  crops.  Schwertz  remarks  very  properly,  that 
this  circumstance  has  led  many  farmers  to  overlook  the  real  advan- 
tages that  belong  to  this  manure.  Cake,  in  fact,  according  to  the 
dryness  or  moistness  of  the  season,  may  act  as  a  manure  either  of 
difficult  or  of  easy  decomposition,  and  so  produce  more  immediate  or 
more  remote  effects.  In  England  about  800  weight  of  oil-cake  per 
acre  are  commonly  applied.  Mr.  Coke,  of  Holkham,  ploughed  in  the 
powdered  cake  about  six  weeks  before  sowing  turnips,  but  it  is  held 
more  economical  and  more  advantageous  to  strew  it  in  fine  powder 
along  the  furrow  with  the  seed.  The  latter  view,  however,  must  not 
be  too  confidently  acted  on  by  farmers  ;  the  general  recommendation 
to  sow  the  fields  with  powdered  cake,  either  some  weeks  before 'or 
some  weeks  after  putting  it  in  the  seed,  and  when  the  plants  have 
already  sprung,  appears  to  be  the  right  one.  We  have  various  ob- 
servations made  by  one  of  our  most  experienced  practical  farmers 
which  prove  that  oil-cake  used  dry  and  without  mixture  often  pro- 
duces the  most  injurious  effects  upon  germination.  In  September, 
1824,  M.  Vilmorin,  desiring  to  make  a  comparative  trial  of  different 
pulverulent  manures,  strewed  a  quantity  of  powdered  colewort-cake 
upon  a  piece  of  red  clover.  Upon  all  the  parts  of  the  field  which 
had  received  other  manures,  applied  in  the  same  way,  the  clover 
sprung  perfectly  ;  but  that  which  had  received  the  oil-cake  continu- 
ed absolutely  naked  ;  the  cake  had  been  employed  in  the  proportion 
of  about  800  cwt  per  acre.  The  same  result  was  also  obtained  in 
a  trial  made  with  vetches  and  gray  winter  peas.*  Duhamel,  refer- 
ring to  similar  facts,  recommends  the  cake  to  be  applied  ten  or 
twelve  days  before  sowing.  In  Flanders,  from  6  to  7  cwt.  per  acre 
is  the  quantity  generally  employed  for  wheat  crops,  and  it  is  scatter- 
ed over  the  surface  before  winter  sets  in,  when  the  grain  is  already 
above  the  ground. 

The  pulp  of  the  beet-root  vihich  has  been  employed  in  the  sugar 
manufactories  of  France  and  Flanders,  is  an  article  which  as  food  for 
cattle  is  known  not  to  be  inferjftr  to  the  root  before  it  has  undergone 
expression,  and  it  contains  nearly  the  same  proportions  of  sugar,  al 
bumen,  &c.  It  is,  therefore,  always  used  as  food  to  as  great  an  ex 
tent  as  possible.  But  the  article  is  kept  with  difficulty,  and  the  pro 
duction  at  times  far  exceeds  the  powers  of  consumption,  so  that  i 
has  to  be  made  into  manure,  for  which  it  answers  excellently.  Tin 
skimmings  and  dregs  which  are  collected  in  the  process  of  suga» 
making,  are  also  available  as  manure.  They  contain  about  the  sam< 
amount  of  azote  or  azotized  matter  as  farm  dung,  and  are  therefor* 

•  Vilnjorin,  in  Malson  Rnstiin<>  vol.  i.  p.  204. 


REFUSE  OF  THE  SUGAR-HOUSE,  ETC.  277 

of  similar  value.  The  animal  charcoal  of  the  sugar  refinery,  after 
it  has  served  its  office  there,  is  an  admirable  manure.  It  is,  in  fact 
bone  or  ivory-black,  mixed  with  the  coagulated  blood  which  has  been 
employed  to  clarify  the  sirup  by  entangling  impurities,  and  a  very 
small  quantity  of  sugar.  This  mixture,  so  rich  in  azotized  princi- 
ples, used  actually  to  be  turned  into  the  sewers  until  the  year  1824, 
when  M.  Payen  showed  its  value  as  manure,  since  which  time  near- 
ly 10,000  tons  have  been  annually  employed  in  ameliorating  the  soil, 
to  the  great  advantage  of  practical  agriculture.  The  importance 
of  the  trade  in  this  residue  of  the  sugar-house,  and  complaints  of  the 
occasional  indiflferent  quality  of  the  article,  attracted  the  attention  of 
the  department  of  the  Inferior-Loire  in  1838,  and  led  to  the  appoint- 
ment of  an  inspector  of  the  manure  shipped  from  the  port  of  Nantz. 
I  may  here  observe,  that  in  testing  a  manure  it  is  by  no  means 
enough  to  limit  attention  to  the  quantity  of  organic  matter  which  it 
contains.  The  only  sure  means  is  to  determitie  the  amount  of  azote  • 
it  is  not  organic  matter,  but  the  amount  of  azotized  organic  matter 
upon  which  almost  alone  depends  the  value  of  the  manure. 

The  residue  of  the  sugar  refinery  is  another  of  those  articles 
which  presents  an  occasional  anomaly  in  its  application,  and  which 
must  not  be  left  unnoticed.  Its  eflfect  upon  the  ground  has  not  only 
been  extremely  variable,  but  it  has  sometimes  happened  that  this 
manure,  laid  on  very  soon  after  coming  from  the  manufactory,  has 
been  found  decidedly  injurious  to  vegetation.  Kept  for  some  time, 
for  a  month  or  two»  in  a  heap  before  being  applied,  its  effect  has  no 
only  been  found  more  certain,  but  also  uniformly  favorable. 

It  is  not  difficult  to  explain  these  divers  and  opposite  influences  : 
the  sugar  contained  in  the  refuse  undergoing  fermentation  yields 
irst  alcohol,  and  than  acetic  and  lactic  acids.  Employed  in  this 
state,  the  substance  must  necessarily  prove  injurious  to  vegetation. 
It  is  only  after  it  has  lain  for  a  sufficient  length  of  time  exposed  to 
the  air,  to  have  had  the  animal  matter  it  contains  changed  into  am- 
monia, and  the  organic  acids  engendered  saturated  with  this  base, 
that  it  becomes  truly  useful  to  vegetation.  The  heap  indeed  then 
shows  alkaline,  not  acid  re-action.* 

The  residue  of  the  starch  manufacturer,  the  fetid  water  which  is 
obtained  in  such  quantity  in  the  process  of  making  starch  from  grain, 
is  a  powerful  manure,  and  ought  not  to  be  suffered  to  run  to  waste. 

The  pulp  or  residue  of  the  potato  which  is  now  produced  in  con- 
siderable quantity  in  the  potato  starch  manufactories,  is  known  to 
be  an  excellent  article  of  food  for  hogs  and  cattle.  Towards  the 
end  of  the  season,  however,  it  is  apt  to  be  of  very  indifferent  quality, 
and  green  food  having  by  this  time  come  in  abundantly,  it  often 
goes  to  the  dung-hill.  In  the  dry  state,  it  is  worth  its  own  weight 
of  farm  dung;  wet,  100  of  the  pulp  may  be  equal  to  about  131  of 
farm-yard  dung.  The  water  which  has  served  for  washing  out  the 
starch  from  the  pulp,  as  in  the  case  of  wheat  and  other  grain,  coa- 
tains  an  organic  substance  which  when  dried  constitutes  pulverulent 

*  Payen  and  Boussingault,  Ann.  de  Chimie,  v.  iii.  p.  95,  36  seJie 
24 


278  ANLMAL   REMAINS. 

Taanure  that  is  equal  to  about  half  its  weight  cf: he  dry  manure  prtv 
pared  from  night  soil,  which  the  French  call  pc  idrette.  M.  Daillj 
made  a  cotnparative  trial  of  these  two  kinds  cf  manure,  and  from 
actual  experiment  found  that  200  parts  of  the  deposite  from  th«  starch 
manufactory  might  be  used  for  100  of  poudrette.  Even  the  water 
that  is  used  in  the  manufacture,  and  from  which  tlie  subsiance  m 
question  is  deposited,  is  an  excellent  manure  when  thrown  upon  the 
ground,  a  circumstance  which  is  by  so  much  the  more  fortimate  that 
this  water  by  standing  putrefies  and  throws  off'  most  utFensive  ex- 
halations. By  using  the  liquor  to  his  fields,  at  once,  M.  Dailly  pre- 
vents every  kind  of  annoyance  to  himself  and  his  neighbors,  and 
moreover  from  his  great  starch  manufactory  he  realizes  in  this  way 
an  additional  profit  which  he  estimates  at  upwards  of  jC60  per  an- 
num. Analysis  has  shown  that  100  of  this  water  from  the  potato 
starch  manufactory  represents  17  of  moist  farm-yard  dung. 

In  cider  countries,  the  ■pulp  of  the  apples  that  have  been  pressed 
is  always  thrown  upon  land  as  manure.  At  Bechelbronu  we  reserve 
it  for  our  Jerusalem  artichokes  ;  in  Normandy  it  is  thought  excel- 
lent for  meadows  and  young  orchards.-  Analysis  of  the  pulp  of  ap- 
ples grown  in  Alsace  shows  that  when  dry  it  contains  a  quantity  of 
azote,  which  places  it  on  the  same  footing  as  farm-yard  dung, 
Sinclair  informs  us  that  in  Herefordshire  the  pulp  of  the  cider  press 
is  made  into  good  manure  by  being  mixed  with  quick-lime  and 
turned  two  or  three  times  in  the  course  of  the  following  summer. 
Doubtless  the  addition  of  lime  will  hasten  the  decomposition  of  the 
woody  matter  of  the  pulp  ;  but  it  strikes  me  that  this  will  take  place 
rapidly  enough  of  itself  in  the  ground  without  contriving  any  means 
of  accelerating  the  process. 

Animal  remains.  The  remains  of  dead  animals  and  the  animal 
matters  obtained  from  the  slaughter  house  are  powerful  manures, 
which  are  much  sought  after  in  places  where  their  value  is  properly 
appreciated.  Scraps  and  the  refuse  of  skin,  hair,  horn,  tendons, 
bones,. feathers,  <fec.,  all  form  invaluable  manure.  The  flesh  of  ani- 
mals which  die,  and  so  much  of  that  of  horses  that  are  slaughtered 
which  cannot  be  used  as  food  for  animals,  may  be  dried  after  having 
been  previously  boiled,  and  then  reduced  to  powder  and  applied  as 
manure.  The  blood  of  slaughtered  animals  is  less  proper  as  food 
for  hogs,  although  it  is  often  used  in  this  way,  than  muscular  flesh ; 
it  even  occasionally  gives  rise  to  serious  diseases  among  these  ani- 
mals. It  is  most  easily  prepared  as  manure,  however,  for  which  it 
answers  admirably  ;  it  is  enough  to  coagulate  it  by  exposure  to  heat, 
and  then  having  broken  it  down,  to  dry  it  in  the  air  or  in  the  stove. 
Liquid  blood  has  been  employed  as  manure,  but  decomposition  then 
takes  place  so  rapidly,  that  the  produc  s  are  exhaled  without  pro- 
ducing much  eff(ect.  This  objection  may  be  remedied  by  two  means, 
either  by  diluting  the  blood  in  a  large  quantity  of  water,  with  which 
the  land  is  then  irrigated,  or  by  mixing  it  with  a  considerable  mass 
of  vegetable  earth,  which  is  then  applied  like  ordinary  manure. 
There  is  even  a  pulverulent  manure  of  which  blood  forms  the  basis, 
|?ropared  in  special  establishments  m  the  vicinity  of  various  large 


BONES.  2T9 

towns.  The  large  quantity  of  azote  contained  in  these  manures 
shows  how  their  value  may  be  such  as  to  permit  of  their  being 
advantageously  exported  to  great  distances  beyond  seas. 

Bones  are  employed  in  agriculture  after  having  had  the  fat  which 
they  contained  extracted  from  them  by  boiling.  They  are  crushed 
by  being  passed  between  the  teeth  or  grooves  of  a  couple  of  cast- 
iron  rollers.  They  must  be  regarded  as  a  manure,  the  action  of 
which  is  of  long  duration,  because  the  animal  matter  contained  in 
them  decomposes  slowly,  protected  as  it  is  by  the  earthy  casing 
which  surrounds  it.  In  England  from  50  to  60  bushels  of  biuiseJ 
bones  per  acre  are  usually  put  upon  land  prepared  for  turnips 

The  employment  of  bones  as  manure  has  given  rise  to  the  most 
various  and  contradictory  observations.  In  certain  circumstancesi 
their  effect  upon  vegetation  has  been  almost  null ;  in  others  their 
action  has  been  decisive  and  most  favorable.  M.  Payen  has  given 
a  solution  of  these  anomalies  which  is  perfectly  satisfactory.  Ac- 
cording to  my  learned  colleague,  bones  in  their  interstices,  contain 
a  quantity  of  fat  of  various  consistency,  which  may  be  removed  by 
long  boiling  in  water  ;  the  average  quantity  of  grease  obtained  from 
fresh  bones  is  about  10  per  cent.  It  has  been  observed  that  this  fat- 
ty matter  diminishes  gradually  in  bones  that  dry  by  long  exposure  ; 
it  even  disappears  almost  entirely  when  they  are  dried  at  a  high 
temperature.  This  happens  from  the  water  which  is  disengaged 
from  the  bony  tissue  by  the  effect  of  evaporation,  being  replaced  by 
fat  melted  by  the  heat.  The  consequence  of  this  is,  that  the  organic 
tissue  of  bone,  which  was  already  sufficiently  rebellious  to  decom- 
position, becomes  still  less  alterable  when  it  is  impregnated  with 
grease.  The  grease,  in  fact,  by  reacting  upon  the  carbonate  of 
lime  of  the  bone,  has  formed  an  earthy  soap  which  long  resists  at- 
mospherical influences  and  change  under  ground. 

It  will  readily  be  understood  that  bones  in  this  condition  can  have 
little  or  no  action  upon  vegetation,  unless  indeed  they  be  reduced  to 
very  fine  powder.  This  alone  will  explain  how  it  may  happen  that 
some  bones,  after  having  remained  four  years  in  the  ground,  have 
been  found  to  have  lost  no  more  than  8  per  cent,  of  their  weight, 
while  those,  the  grease  of  which  has  been  removed  by  boiling  water, 
have  lost  in  the  same  space  of  time  from  25  to  30  per  cent,  of  their 
weight.* 

These  observations  of  M.  Payen  show  how  completely  Schwertz 
was  mistaken  when  he  ascribed  the  indifferent  quality  of  the  ma- 
nure prepared  from  old  bones,  or  from  bones  that  had  been  boiled, 
to  the  absence  of  fat,  which  he  regards,  I  know  not  on  what 
authority,  as  a  substance  extremely  favorable  to  vegetation.  It  is 
not  very  obvious  how  fatty  substances  should  act  as  manures.  I 
myself  ascertained,  from  experiments  made  some  years  ago  with 
a  view  to  test  the  conclusions  of  an  agriculturist  who  ascribed 
the  good  eflfects  of  cake  to  the  fatty  matters  which  it  containeo, 
that  rape-oil  had  no  kind  of  favorable  influence  upon  the  growth 

*  Payen,  Maison  Rustlque  v.  i.  p.  194. 


^80  GRAVES WOOLLEN  RAGS,  ETC. 

of  wheat.  I  have  said  nothing  here  upon  the  importance  of  tn« 
earthy  matter  of  bones,  particularly  of  the  calcaieons  phosphate 
which  they  contain,  but  which  is  nevertheless  acknowledged  to  be 
of  great  importance. 

The  refuse  from  the  glue -maker'*  s,  washed  and  pressed,  contains 
all  the  animal  matters  which  have  resisted  the  action  of  boiling 
water,  such  as  portions  of  tendinous  and  skinny  substance,  hair, 
pieces  of  bone,  of  horn,  and  of  flesh,  a  calcareous  soap,  and  earthy 
matters.  This  mixture  putrefies  rapidly  ;  but  dried,  it  may  be  pre- 
served for  a  great  length  of  time.  Analyzed  dry,  it  yields  about  4 
per  cent,  of  azote.  From  4  to  5  cwt.  per  acre  are  employed,  but  it 
is  necessary  to  manure  every  year. 

The  refuse  of  the  tallow-melter,  graves,  as  it  is  called,  a  residue 
consisting  in  great  part  of  the  membranes  which  have  enveloped 
the  fat  of  our  domestic  animals,  mixed  with  a  little  blood,  some 
flesh,  and  bony  matter,  and  grease,  has  hitherto  been  em^-Zoyed 
almost  exclusively  as  food  for  dogs.  Of  late,  however,  graves  have 
been  used  as  manure,  and  analysis  shows  that  this  substance  must 
be  estimated  as  equal  to  about  3|,  farm-dung  being  fixed  at  1. 
Used  in  this  proportion,  graves  produce  a  marked  eflfect.  The 
action  of  graves,  which  may  be  thrown  on  in  fragments  and  dry,  or 
after  having  been  steeped  in  hot  water,  and  reduced  to  the  state 
of  a  pulp,  will  continue  for  three  or  four  years. 

Shreds  o^  woollen  rags  form  a  good  manure  for  vines  and  olive- 
trees  especially,  though  they  are  also  available  in  husbandry  of 
every  description.  The  large  proportion  of  azote,  and  the  small 
quantity  of  water  contained  in  woollen  rags,  constitute  them  not  only 
one  of  the  richest  manures,  but  also  one  of  those  that  is  most  easily 
transported  ;  25  cwts.  per  acre  of  woollen  rags,  the  cost  of  which,  in 
J' ranee,  may  be  about  £3,  have  been  found  sufficient  as  manure  for 
three  years.  The  slowness  with  which  wool  decomposes,  indeed, 
causes  its  action  to  be  continued  during  six  or  eight  years.  Tvventy- 
nve  cwt.  of  woollen  rags  may  be  held  equivalent  to  upwards  of  40 
tons  of  farm-dung,  which,  at  the  price  of  5^  lOd.  per  ton,  would  cost 
jCl2  165.  At  the  end  of  three  years,  M.  Delonchamps,  an  excellent 
practical  farmer,  gives  his  land  a  dressing  of  farm-dung  for  three 
years  more,  when  he  returns  to  the  wool.  Before  spreading  rags 
they  must  be  cut  into  pieces,  which  is  effected  either  by  a  machine, 
or  by  a  piece  of  scythe-blade  fixed  in  a  block  of  wood.  In  England, 
the  quantity  of  woollen  rags  allowed  to  the  acre  is  generally  about 
13  cwt.  Sinclair  says  that  they  are  best  suited  for  dry  and  sandy  or 
chalky  soils,  and  this  because  they  attract  moisture.  I  have  not 
found  the  fact  to  be  so.  In  the  very  dry  soil  of  a  vineyard  manured 
with  this  article,  1  have  found  the  pieces  to  decompose  with  extreme 
slowness,  and,  up  to  this  time,  the  eflfect  upon  the  vines  has  been 
scarcely  perceptible. 

The  raspings  and  shavings  of  horn  form  a  manure  of  great  power, 
that  seems  applicable  to  ,4very  variety  of  soil.  In  England,  about 
(0  bushels  per  acre  are  usually  allowed. 

Tendons  J  trimmings  of  hides,  hair,  feathers,  <5fC.,  are  manures  very 


SHELLS MUD.  281 

analogous  to  the  last,  and  of  which  the  value  may  be  estimated  from 
the  quantity  of  azote  which  they  severally  contain.  This  value  once 
determined,  every  farmer  knows  the  quantity  which  he  must  lay 
upon  his  land  ;  and  lie  thus  proceeds  upon  a  much  more  rational 
foundation  than  when  he  takes  for  his  guide  one  or  other  of  those 
vague  and  arbitrary  indications  that  iiave  been  given.  Sinclair,  for 
example,  would  have  us  lay  on  nine  bushels  of  feather  rubbish  to  the 
acre,  and  Schwertz  recommends  from  four  to  five  times  as  much 
more  Nothing,  in  fact,  is  more  arbitrary  and  uncertain  than  to 
estimate  sucii  materials  by  the  bulk ;  it  must  be  obvious  that  the 
weight  of  a  bushel  of  hide  trimmings,  of  horn-shavings,  and  of 
feather-rubbish,  must  differ  very  widely,  not  only  with  reference  to 
one  another,  but  also  according  to  the  state  of  division  in  which  each 
is  measured.  As  a  general  rule,  it  is  by  weight,  and  weight  alone, 
that  the  quantity  of  manure  must  be  estimated. 

Shells  and  mud  from  the  sea-shore  and  the  bottoms  of  rivers,  are 
matters  that  are  not  often  very  highly  azotized  ;  nevertheless  they 
may  contain  an  equivalent  of  the  all-important  element,  azote,  which 
may  bring  them  near  to  wet  farm-yard  dung  in  point  of  value.  The 
abundance  of  such  matters  in  certain  situations  makes  them  ex- 
tremely useful.  The  alkaline  and  earthy  salts,  which  they  generally 
contain  in  considerable  quantity,  also  add  to  their  fertilizing  proper- 
ties. The  sea-sand  which  is  employed  in  Brittany  under  the  name 
oi  marl,  (merl,)  consists,  in  great  part,  of  the  remains  of  corallines, 
madrepores,  and  shells,  mixed  with  a  few  hundredths  of  highly 
azotized  organic  manner.  This  marine  marl  is  found  in  great 
abundance  at  the  mouths  of  the  river  of  Morlaix,  where  there  is  a 
considerable  traffic  carried  on  in  the  article.  It  is  said  to  be  repro- 
duced, new  banks  of  it  being  met  with  from  time  to  time.  It  is 
obtained  by  dredging  from  barges,  and  the  process  is  only  allowed 
to  go  on  from  the  15th  of  May  to  the  15th  of  October,  when  the 
quays  of  the  town  of  Morlaix  are  seen  covered  with  the  produce. 
It  is  carted  to  a  distance  of  five  leagues  inland.  A  barge-load 
weighing  seven  tons,  sells  at  from  6^.  Qd.  to  8.y.  This  same  species 
of  marl  is  now  obtained  upon  the  coast  of  Plancourtrez  and  in 
the  roads  of  Brest.  It  has  also  been  discovered  near  the  mouth 
of  the  river  Quimpert.  It  appears,  finally,  that  the  shell  sand  so 
much  employed  by  the  farmers  of  Devonshire  and  Cornwall  is  of 
the  same  essential  nature. 

In  the  neighborhood  of  Morlaix,  from  five  to  six  tons  per  acre  of 
this  calcareous  sand  are  employed  upon  light  dry  soils  ;  from  eleven 
to  twelve  tons  are  given  to  clayey  lands.  This  quantity  would 
probably  be  too  great  for  porous  and  damp  soils,  inasmuch  as  sea- 
marl  belongs  to  the  class  oi'  warm  manures  ;  that  is  to  say,  it  under 
goes  speedy  decomposition.  There  can  be  no  doubt  that  sea-marl 
acts  further,  in  virtue  of  the  calcareous  matter  which  it  contains, 
and  also  of  its  merely  mechanical  properties  upon  the  strong  argilla- 
ceous lands  of  Brittany,  for  which  sand  alone  is  an  excellent  im- 
prover. It  is  also  to  the  carbonate  of  lime  which  it  contains,  that 
"Is  good  effects  upon  lands  that  show  an  inflorescence  of  iron  pyrites 

24* 


£82  SHELL ^MARL. 

must  be  ascribed.  It  is  well  to  lay  this  shell-marl  upon  the  land 
shortly  after  it  is  taken  from  the  sea  :  by  long  exposure  to  the  air, 
it  suffers  disaggregation  and  loses  a  portion  of  its  good  qualities. 

There  is  another  kind  of  sea-sand  called  Irez,  which  forms  banks 
in  the  neighborhood  of  Morlaix,  and  which  is  known  under  the  name 
of  ianifue  on  the  northern  shores  of  France,  which  is  favorable  to 
vegetation,  particularly  after  it  has  been  washed  and  freed  from  the 
greater  part  of  the  salt  which  it  contains.  It  is  thrown  upon  the  land 
in  larger  quantity  than  the  marl.  The  small  quantity  of  animal  mat- 
ter which  it  contains  putrefies  and  is  lost  when  it  ren^ains  exposed 
to  the  air  for  any  length  of  time,  so  that  a  distinction  has  been  made 
between  fresh  or  live  trez^  and  old  or  dead  Irez,  the  one  being  the 
article  as  ii  comes  from  the  sea,  the  other  after  it  has  been  exposed 
some  time  on  the  shore  ;  the  article  which  has  been  exposed  un- 
doubtedly contains  a  smaller  quantity  of  organic  matter  than  that 
which  is  quite  fresh.  This  variety  of  sea-sand  is  particularly  avail- 
able upon  close  and  clayey  lands,  which  sometimes  receive  as  many 
as  sixteen  tons  per  acre  with  advantage  ;  lighter  lands,  of  course 
require  much  less. 

Shells,  sand,  slime,  and  sea-weed,  are  not  the  only  useful  mate- 
rials supplied  to  agriculture  by  the  sea ;  fish,  or  their  offal,  is  fre- 
quently employed  as  manure.  The  practice  of  manuring  with  fish 
is  very  old,  and  is  universal  wherever  it  can  be  had  recourse  to 
I  have  already  had  occasion  to  say,  that  at  the  period  of  the  con- 
quest of  America,  the  Spaniards  found  it  established  among  the 
Indians,  on  the  shores  of  the  Pacific  ocean.  The  lands  are  oc- 
casionally manured  with  fish  along  the  sea-board  of  Great  Britain 
and  Ireland,  and  the  low  lands  of  Lincolnshire,  Cambridgeshire, 
and  Norfolk,  also  receive  occasional  supplies  of  the  same  power- 
ful maimre.  The  offal  of  the  herring  fishery,  of  cod,  of  skate,  and 
of  the  pilchard,  in  Cornwall,  the  dog-fish  entire,  and  other  kinds, 
that  are  either  less  esteemed,  or  that  are  caught  in  quantities  greater 
than  can  be  consumed  as  food,  are  all  admirable  manures.  We  have 
been  recommended  to  mix  the  fish  or  fish-offal  with  quick-lime ;  but, 
unless  in  certain  circumstances,  the  practice  is  very  questionable  ; 
the  addition  is  probably  only  proper  where  the  materials  are  ex- 
ceedingly oily,  as  is  the  case  with  pilchards,  herrings,  &c.  :  an 
earthy  soap  is  then  formed  which  prevents  the  injurious  effects  upon 
vegetation  which  wholly  oleaginous  matters  scarcely  fail  to  produce. 
One  analysis  of  codfish,  which  I  made  along  with  M.  Payen,  gave 
us  a  proportion  of  azote  of  nearly  seven  per  cent.  This,  of  itself,  is 
enough  to  explain  wherefore  the  flesh,  the  cartilages,  and  the  bones 
of  fishes  should  be  found  such  energetic  manures. 

The  slime  deposited  by  rivers  also  yields  manure  which  may  be 
employed  to  much  advantage.  The  Nile,  which  periodically  inun- 
dates the  plains  of  Lower  EgypU  «)wes  its  fertilizmg  action  to  the 
slime  which  it  contains,  and  which  it  deposites  before  it  again  recedes 
into  its  bed.  On  the  banks  of  the  Durance,  the  mud  or  slime  depos- 
ited by  the  river  is  carefully  collected  for  distribution  over  the  fields 
in  its  vicinity.     The  waters  of  this  river  are  frequently  turbid  and 


SOOT.  283 

improper  for  irrigation,  until  they  have  deposited  the  slime  which 
they  hold  in  suspension  ;  the  waters  are  therefore  turned  into  canals 
for  the  purpose  of  deposition  before  they  are  let  upon  the  land  ;  and 
such  is  the  quantity  of  slime  that  is  precipitated,  that  two  or  three 
gatherings  of  it  are  made  in  the  course  of  the  year.  It  is  dug  out 
and  thrown  upon  the  banks  to  dry  ;  reduced  to  powder,  it  is  fit  to  be 
laid  upon  the  land  ;  and  such  is  its  fertilizing  power,  that  a  field 
which  yielded  but  four  for  one,  has  been  brought  to  yield  twelve  for 
one  by  its  means.* 

Wood  and  coal  soot,  and  Picardy  ashes.  Soot  has  been  known 
tor  a  long  period  as  a  useful  manure.  M.  Braconnot,  in  the  soot  of 
a  chimney  where  wood  had  been  the  fuel,  found  the  following  in- 
gredients : 

Ulmicacid 30.0 

Azotic  matter,  soluble  in  water 20.0 

Insoluble  carbonated  matter 3.9 

Silica 1.0 

Carbonate  of  lime 14.7 

Carbonate  of  magnesia  (traces  of) 

Sulphate  of  lime 0.5 

Ferruginous  phosphate  of  lime 1.5 

Chloride  of  potassium 0.4 

Acetate  of  potash 4.1 

Acetate  of  lime 5.7 

Acetate  of  magnesia 0.5 

Acetate  of  iron  (traces  of) 

Acetate  of  ammonia 0.2 

An  acrid  and  bitter  element 0.5 

Water 12.5 

100.0 

The  analysis  which  M.  Payen  and  I  made  of  wood  and  coal  soot, 
confirms  the  presence  of  the  azotized  principle  detected  by  M.  Bra- 
connot. A  considerable  trade  is  carried  on  in  soot  for  agricultural 
purposes  in  large  towns  ;  it  is  thrown  upon  clovers  and  young  wheats, 
in  the  proportion  of  about  20  bushels  lo  the  acre.  Some  have  re- 
commended that  it  should  be  mixed  with  lime  ;  but  as  soot  always 
contains  salts  having  a  base  of  ammonia,  the  practice  is  evidently 
objectionable,  unless  indeed  the  object  be  to  get  rid  of  that  which  is 
most  useful  in  the  article,  which  will  be  effectually  accomplished  by 
adding  lime  to  it.  The  proper  procedure  is  to  employ  the  soot 
without  admixture  during  calm  or  wet  weather.  In  Flanders,  the 
colewort  beds  destined  for  transplanting  are  very  generally  manured 
with  soot,  which  is  believed  to  have  the  property  of  preserving  the 
young  plants  from  the  attacks  of  insects.  In  the  neighborhood  of 
Lisle,  they  give  from  55  to  60  bushels  of  soot  per  acre.  Schwertz 
appeals  to  many  facts  which  go  far  to  satisfy  us  that  the  eflfects  of 
soot  upon  clovers  are  particularly  advantageous  ;  he  says,  moreover, 
that  coal  soot  is  preferable  to  wood  soot.  The  superior  properties 
of  coal  soot  are  evidently  due  to  two  causes :  first,  it  is  more  dense 

*  Belleval,  in  Annals  of  French  Agriculture,«2d  series,  vol.  xiv.  p.  261.  The  beds  of 
many  of  the  oozy-bottomed  rivers  in  England  near  the  sea  are  inexhaustible  sources 
of  the  most  valuable  manure.  The  bed  of  the  Thames,  between  London  Bridge  and 
Putney  Bridge  at  low  wau;r,  ii;  a  true  i,(^\t\  mine  if  it  were  but  richtly  used. — Eno.  Ed 


B84  PICARDY  ASHES. 

than  wood  soot,  and  in  a  given  bulk  actually  contains  a  !arger  quan 
tity  of  matter  ;  secondly,  I  have  found  that,  for  equal  weights,  coal 
soot  contains  the  larger  quantity  of  azote. 

Picardy  ashes  are  prepared  by  the  slow  and  imperfect  combustion 
of  the  pyritic  turf  which  is  dug  up  in  the  department  of  the  Aisne 
for  the  manufacture  of  sulphate  of  iron  and  of  alum.  Tiiis  turf  piled 
up,  heats,  and  finally  takes  tire  ;  the  combustion  continues  for  about 
a  month,  abundance  of  sulphureous  vapors  being  disengaged.  The 
residue  is  a  gray  ash,  still  containing  a  quantity  of  carbonaceous 
matter,  which  is  found  very  advantageous  in  the  way  of  top-dress- 
ing for  meadows.  It  might  be  maintained  that  the  utility  of  such 
ashes  depends  solely  on  the  sulphate  of  lime  which  they  contain  ; 
but  it  is  ascertained  that  they  are  much  more  active  as  maimre  than 
this  substance  employed  by  itself;  analysis,  in  fact,  explains  in  some 
degree  the  fertilizing  powers  of  these  ashes,  by  showing  that  they 
contain  more  than  4  per  cent,  of  azote,  to  say  nothing  of  the  saline 
matters  of  which  vegetables  are  so  greedy.  It  is  extremely  proba- 
ble that  during  the  slow  incineration  of  the  turf,  there  is  a  quantity 
of  sulphate  of  ammonia  produced. 

The  ashes  which  remain  after  the  lixiviation  of  the  pyritic  and 
aluminous  lignites  which  are  mined  for  the  purpose  of  making  green 
vitriol,  are  analogous  to  Picardy  ashes,  and  are  employed  with  equal 
success  in  agriculture.  At  Forges-les-Eaux,  the  pyritic  earths  after 
-ixiviation  are  mixed  with  a  quarter  of  their  weight  of  turf  ashes, 
and  form  an  active  manure  which  is  employed  very  extensively  in 
the  country  around  the  town  of  Bray  in  France  :  it  is  equally  adapt- 
ed to  meadows  and  to  land  under  roots,  such  as  potatoes  or  turnips, 
green  crops  or  corn.  Analysis  shows  these  ashes  to  have  the  fol- 
owing  composition : 

Soluble  organic  matter 2.7 

Insoluble  humus ....  49.8 

Sulphate  of  protoxide  and  of  peroxide  of  iron 1.8 

Fine  sand 39.0 

Sulphuret  of  iron  )                ^       g^ 

Peroxide  of  iron    \ 

100.0 

The  vitriolic  ashes  of  Forges-les-Eaux  are  more  highly  azotized 
than  those  of  Picardy  ;  they  contain  2.72  per  cent,  of  azote. 

The  effect  of  the  imperfect  combustion  of  these  pyritic  turfs,  the 
product  which  results  from  it,  explains  to  a  certain  extent  the  bene- 
ficial effects  of  the  practice  o{ paring  and  burning,  an  important  and 
widely  spread  practice,  the  utility  of  which  it  would  be  difficult  to 
understand,  were  it  not  connected  in  some  way  with  the  production 
of  ammoniacal  ashes. 

The  useful  effects  of  paring  and  burning,  are,  in  all  probability, 
connected  with  the  destruction  of  organic  matter,  very  poor  in  azo- 
tized  principles  ;  in  the  transformation  of  the  surface  of  the  soil  into 
a  porous,  carbonaceous  earth,  made  apt  to  condense  and  retain  the 
ammoniacal  vapors  disengaged  during  the  combustion  ;  lastly,  by 
the  production  of  alkaline  and  earthy  salts,  which  are  familiarly 
known  to  exert  a  most  beneficial  influence  upon  vegetation.     These 


MANURES.  285 

conditions  seem  so  entirely  those,  the  object  of  which  it  is  to  realize 
by  paring  and  burning,  that  in  order  to  make  the  operation  favorable 
to  the  soil  which  undergoes  it,  the  vegetable  matter  which  it  has 
produced,  must  of  necessity  be  transformed  into  black  ashes ;  when 
it  goes  beyond  this,  as  Mr.  Hoblyn  has  well  observed,  when  the  in- 
cineration is  complete,  and  the  residue  presents  itself  as  a  red  ash, 
the  soil  may  be  struck  with  perfect  barrenness  for  the  future.  The 
burning,  therefore,  that  was  not  properly  managed,  that  led  to  the 
complete  incineration  of  all  the  organic  matter,  would,  for  the  same 
reason,  have  a  very  bad  effect  in  the  preparation  of  the  Picardy  ash- 
es ;  which  might  indeed  act  in  the  same  way  as  turf  ashes  from  the 
hearth  and  oven,  but  which,  deprived  of  all  azotized  principles,  would 
not  ameliorate  the  ground  in  the  manner  of  organic  manures. 

I  have  frequently  seen  the  process  of  burning  pertormed  in  the 
steppes  of  southern  America.  Fire  is  set  to  the  pastures  after  the 
grass  which  covers  them  has  become  dry  and  woody ;  the  flame 
spreads  with  inconceivable  rapidity,  and  to  immense  distances.  The 
earth  becomes  charred  and  black  ;  the  combustion  of  those  parts 
that  are  nearest  to  the  surface,  however,  is  never  complete  ;  and  a 
few  days  after  the  passage  of  the  flame,  a  fresh  and  vigorous  vege- 
tation is  seen  sprouting  through  the  blackened  soil,  so  that  in  a  few 
weeks  the  scene  of  the  desolation  by  fire,  becomes  changed  into  a 
rich  and  verdant  meadow. 


ANIMAL   EXCREMENTS. 

Horse-dung.  The  composition  of  horse-dung  would  lead  us  to 
infer  that  its  action  must  be  more  energetic  than  that  of  cow-dung. 
Nevertheless,  agriculturists  frequently  consider  it  as  of  inferior  qual- 
ity. This  opinion  is,  even  to  a  certain  extent,  well  founded.  Thus 
although  it  be  acknowledged  that  horse-dung  covered  in  before  it  has 
fermented,  yields  a  very  powerful  manure,  it  is  known  that  in  general 
the  same  substance,  after  its  decomposition,  affords  a  manure  that  is 
really  less  useful  than  that  of  the  cow-house.  This  comes  entirely 
from  the  fact  that  the  droppings  of  the  stable,  by  reason  of  the  small 
quantity  of  moisture  they  contain,  present  greater  difficulties  in  the 
way  of  proper  treatment  than  those  from  the  cow-house.  Mixed 
with  litter  and  thrown  loosely  upon  the  dung-hill,  horse-dung  heats 
rapidly,  dries,  and  perishes  :  unless  the  mass  be  supplied  with  a  suf- 
ficient quantity  of  water  to  keep  down  the  fermentation,  and  the 
access  of  the  air  be  prevented  by  proper  treading,  there  is  always, 
without  the  least  doubt,  a  considerable  loss  of  principles,  which  it  is 
of  the  highest  importance  to  preserve.  I  can  give  a  striking  instance 
of  this  fact  in  the  changes  that  happen  in  the  conversion  of  horse- 
dung  into  manure  in  the  last  stage  of  decomposition  :  fresh  horse- 
dung  in  the  dry  state  contains  2.7  per  cent,  of  azote.  The  same 
dung  laid  in  a  thick  stratum  and  left  to  undergo  entire  decomposition, 
gave  a  humus  or  mould,  from  which,  reduced  to  dryness,  no  more 
than  one  per  cent,  of  azote  was  obtained.  I  add,  that  by  this  fermen- 
|ation  or  decomposition,  the  dung  had  lost  nine  tenths  of  its  weigtt 


280  HORSE-DUNG. 

From  these  numbers  every  one  may  judge  how  great  had  been  the 
ioss  of  azotized  principles.  In  practice,  however,  little  care  is  be- 
stowed on  the  preparation  of  horse-dung  ;  the  fermentation  is  rarely, 
if  ever,  pushed  to  this  extreme  point  indeed  ;  but  it  is  not  the  less 
true  that  it  is  constantly  approached  in  a  greater  or  less  degree  ;  and 
that  the  consequences,  although  not  altogether  so  unfavorable  as 
those  which  I  have  particularly  signalized,  are  nevertheless  extremely 
destructive.  A\l  enlightened  agriculturists  have,  therefore,  long 
been  aware  of  the  attention  necessary  to  the  management  of  horse- 
dung,  which  requires  a  degree  of  care,  that  may  be  perfectly  well 
dispensed  with  when  the  business  is  to  convert  the  dejections  of  horn- 
ed cattle  into  manure.  To  obtain  the  best  results  in  the  management 
of  horse-dung,  it  appears  to  be  absolutely  necessary  to  give  it  a 
much  larger  quantity  of  moisture  than  it  can  ever  receive  from  the 
urine  of  the  animal  ;  if  it  be  not  watered  it  necessarily  heats,  dries, 
and  loses  both  in  weight  and  quality  ;  while,  by  being  kept  properly 
moist,  it  produces  a  manure,  which  half  rotted,  is  of  quality  superior, 
or  at  all  events  equal,  to  the  same  weight  of  cow-dung. 

M.  Schattenmann,  who  has  the  produce  of  stables  containing  two 
hundred  horses  to  manage,  follows  a  process  of  the  most  commend- 
able description  in  the  preparation  of  his  manure,  and  which  is 
attended  with  the  very  best  results.  His  dunghill  stance,  of  no  great 
depth,  is  about  440  yards  square  in  superficies,  and  divided  into  two 
equal  portions.  The  bottom  of  this  stance  is  so  arranged  as  to  pre- 
sent two  inclined  planes,  which  bring  all  the  liquids  that  drain  from 
it  to  the  middle,  where  there  is  an  ample  tank  for  their  reception, 
furnished  with  a  pump  for  their  redistribution  to  the  dunghill.  There 
is  also  another  spring-water  pump  destined  to  supply  the  water  that 
is  necessary  to  preserve  the  dung-heap  in  an  adequate  state  of  moist- 
ness.  The  latter  auxiliary  is  quite  indispensable  ;  the  quantity  of 
water  necessary  is  so  considerable  when  masses  of  such  magnitude 
are  to  be  treated,  that  we  cannot  trust  to  any  casual  source  of  supply . 
The  two  portions  of  the  area  are  alternately  piled  with  the  dung  as 
it  comes  from  the  stables  ;  it  is  heaped  to  the  height  of  10,  12,  or 
14  feet ;  it  is  trodden  down  carefully,  as  it  is  evenly  spread,  and 
plentifully  watered  from  the  spring-water  pump.  Due  consolidation, 
and  a  state  of  constant  humidity,  are  the  two  conditions  that  are  the 
most  indispensable  to  the  successful  preparation  of  horse-dung.  M. 
Schattenmann  is  in  the  habit  of  adding  to  the  liquid,  saturated  with 
the  soluble  matters  of  the  dunghill,  a  quantity  of  sulphate  of  iron  in 
solution,  or  of  sulphate  of  lime  (gypsum)  in  powder  ;  he  also  throws 
the  same  salts  upon  the  surface  of  his  heap  :  the  object  of  this  is 
evidently  to  transform  into  sulphate,  the  volatile  carbonate  of  ammo- 
nia formed  in  the  course  of  the  decomposition,  and  so  to  prevent  its 
escape  and  loss.  By  these  means  a  pasty  manure,  as  rich  as  that 
which  is  yielded  by  horned  cattle,  and  of  a  quality,  the  excellence 
of  which  is  proclaimed  by  the  remarkable  crops  that  cover  the  lands 
which  receive  it,  is  produced  in  the  course  of  two  or  three  months.* 


Bchattenmann  Annales  de  Chimie,  3e  86rie,  vol.  iv.  p  117. 


HORSE-DtTNG.  287 

It  is  almost  useless  to  add,  that  great  care  must  be  taken  not  to  in- 
troduce too  large  a  quantity  of  sulphate  of  iron,  which  might  have 
a  prejudicial  influence  upon  vegetation,  into  the  dunghill  or  the 
drainings  from  it.  In  making  use  of  sulphate  of  lime  there  is  noth- 
ing to  fear  on  this  score  ;  this  salt  in  excess  would  be  rather  favor- 
able than  hurtful ;  in  general,  gypsum  is  certainly  the  preferable 
substance,  both  on  account  of  its  never  doing  mischief,  and  of  its 
greatly  inferior  price.* 

Farmers  generally  advise  horse-dung  to  be  reserved  for  argilla- 
ceous, deep,  and  moist  soils ;  this  recommendation  is  given  in  con- 
nection with  the  manure  that  is  obtained  by  the  usual  imperfect  pro- 
cess of  preparation.  With  regard  to  the  horse-dung,  prepared  in  the 
manner  which  I  have  just  described,  and  as  practised  by  M.  Schat- 
tenmann,  it  is  adapted  to  soils  of  all  kinds  ;  and  if  it  differs  from 
the  dung  of  the  cow-house,  it  is  only  by  its  superior  quality.  This 
last  fact  is  at  once  explained  by  the  elementary  analysis  of  the  ex- 
crements of  a  horse  fed  upon  hay  and  oats. 

100  parts  of  the  urine  of  the  animal  so  fed,  yielded  12.4  of  dry 
extract,  the  composition  of  which  was  as  follows  : 

In  the  state  of  extract.        In  the  liquid  state. 

Carbon 36.0  4.46 

Hydrogen 3.8  0.47 

Oxygen 11.3  1.40 

Azote 12.5  1.55 

Salts ..36.4  4.51 

Water •   "  87.61 

100.0  100.00 

The  droppings  of  the  same  horse  after  drying,  gave  24.7  of  fixed 
matter,  the  analysis  of  which  indicated  : 

Dry  excrement.  Moist  excrement. 

Carbon ..38.7  9.56 

Hydrogen 5.1  1.26 

Oxygen 37.7  9.31 

Azote 2.2  0.54 

Salts 16.3  4.02 

Water "  75.31 

100.0  100.00 

The  dung  of  horned  cattle  is  often  extremely  watery ;  it  is  espe- 
cially so  when  furnished  by  animals  kept  upon  gieen  food  ;  this  ex 
treme  humidity  renders  its  preparation  easy.  Its  equivalent  number 
is  higher  than  that  of  horse-dung  ;  it  is,  in  fact,  less  highly  azotized, 
and  consequently  less  active.  If  the  food  have  a  great  effect  upon 
the  quality  of  the  manure,  it  is  quite  certain  that  the  circumstances 
or  states  of  the  cattle  have  an  effect  which  is  scarcely  less  remark- 
able. Milch  cows  and  cows  in  calf  always  furnish  a  manure  that  is 
less  highly  azotized  than  stall-fed  and  laboring  oxen  ;  and  this  is 
readily  understood  :  the  azotized  principles  of  the  food  are  diverted 
to  secretions,  which  concur  in  the  development  of  a  new  being  in 
the  one  case,  in  t'le  production  of  milk  in  the  other  ;  for  the  same 

•  Every  farmer  who  should  have  something  like  a  cart  or  v^^agon-load  of  gypstun 
brought  to  the  farm  every  year  would  find  his  profit  from  the  practice. — Ewa.  Ea. 


288 

reason  the  dejections  of  young-  animals,  all  things  else  being  equal 
furnish  a  manure  of  less  power  and  value  than  those  of  adult  ani- 
mals. I  shall  have  occasion  to  recur  to  this  important  subject 
-vhich  has  never  yet  been  sufficiently  studied. 

The  urine  and  excrements  of  a  milch  cow,  which  is  giving  about 
12  pints  of  milk  per  diem,  have  shown  upon  analysis,  the  following 
quantities  of  elements  :  100  of  the  urine  contained  H.7  of  dry  ex- 
tract, and  had  this  composition  : 

Urine  dry.  Urine  liquid. 

Carbon 27.2  3.18 

Hydrogen 2.6  0.30 

Oxygen 26.4  3.09 

Azote 3.8  0.44 

Salts 40.0  4.68 

Water 0.0  88.31 

100.0  100.00 

100  of  fresh  excrement  left  on  drying  9.4  of  dry  substance,  and  in 
each  state  contained  : 

Excrement  dry.  Excrement  moist. 

Carbon 42.8  4.02 

Hydrogen 5.2  0.49 

Oxygen 37.7  3.54 

Azote 2.3  0.22 

Salts 12.0  1.13 

Water 0.0  90.60 

100.0  100.00 

Hog's  dung.  From  all  I  have  seen,  I  conclude  that  hogs  well 
kept  and  put  up  to  fatten,  yidd  dejections  which  are  highly  azotized, 
and  which  must  consequently  furnish  a  manure  of  excellent  quality. 
Schwertz  has,  indeed,  ascertained  that  this  manure  acts  more  pow- 
erfully than  cow-dung. 

Sheep-dung  is  one  of  the  most  active  of  manures,  a  fact  which  is 
confirmed  by  analysis ;  for  it  is  by  no  means  watery,  and  in  the 
usual  state  contains  upwards  of  one  per  cent,  of  azote.  The  mode 
of  managing  sheep  generally  implies  that  they  manure  the  ground 
immediately.  Schwertz  calculates  that  in  the  course  of  a  night,  a 
sheep  will  manure  something  more  than  a  square  yard  of  surface  ; 
at  Bechelbronn  we  have  found  the  quantity  manured  to  be  about  4 
square  feet.     The  following  are  the  details  of  one  experiment : 

Two  hundred  sheep  were  folded  for  a  fortnight  upon  a  rye-stubble, 
of  an  extent  which  gave  as  nearly  as  possible  four  square  feet  of 
surface  per  sheep.  The  manuring  thus  effected  was  found  to  pro- 
duce a  maximum  effect  upon  the  crop  of  turnips  which  followed  the 
rye. 

Pigeon's  dung  is  known  as  a  hot  manure,  and  of  such  activity 
that  it  must  be  used  with  discretion.  Pigeon's  dung  is  available  for 
crops  of  every  description  ;  Schwertz  has  made  use  of  it  for  a  long 
time,  and  always  with  the  greatest  success,  mixed  with  coal  asheS; 
upon  clovers.  The  Flemish  farmers  procure  pigeon's  dung  from 
the  department  of  the  Pas  de  Calais,  where  there  are  a  great  num- 
ber of  dove-cotes,  one  of  which,  containing  from  six  hundred  to  six 
hundred  and  fifty  pigeons,  will  let  for  the  sum  of  about  £i  per  annum, 


I 


GtJANO.  289 

mere.y  for  the  sake  of  the  dung ;  the  quantity  yielded  in  this  time 
may  be  about  a  wagon-load.  In  the  neighborhood  of  Lisle,  this 
manure  is  applied  particularly  in  the  cultivation  of  flax  and  tobacco. 
According  to  M.  Cordier,  the  dung  of  between  seven  hundred  and 
eight  hundred  pigeons  is  sufficient  to  manure  nearly  2^  acres  of 
ground.  The  dung  of  three  hundred  and  twelve  pigeons!^  therefore, 
would  suffice  for  an  acre.  The  value  of  pigeon's  dung  may  be  es- 
timated from  the  large  proportion  of  azote  which  it  contains  ;  that 
which  I  analyzed  from  Bechelbronn  gave  8^  per  cent,  of  this  prin- 
ciple, a  result  which  ought  not  to  excite  surprise  when  it  is  known 
that  the  white  matter  that  appears  in  the  excrements  of  birds,  con- 
sists of  nearly  pure  uric  acid.  The  manure  of  the  hen-house  is 
nearly  or  quite  as  good  as  pigeon's  dung. 

Guano  is  a  manure  of  the  same  nature  as  pigeon's  dung,  and  the 
use  of  which,  long  familiar  on  the  coasts  of  Peru,  has  lately  extend- 
ed to  these  countries,  the  article  being  now  imported  in  large  quan- 
tities, both  from  the  South  American  and  African  coasts.  Guano 
appears  to  be  the  result  of  the  accumulation  for  ages  of  the  excre- 
ments of  the  sea-fowl,  which  live  and  nestle  in  the  islets,  in  the 
neighborhood  of  the  great  southern  continents  of  the  new  and  old 
world.  The  mass  in  many  places  forms  beds  of  between  60  and  70 
feet  in  thickness.  The  principal  places  whence  guano  is  obtained, 
are  the  Chinche  islands  near  Pisco  ;  but  other  deposites  of  the  sub- 
stance are  known  to  exist  more  to  the  south, — in  the  islets  of  Iza 
and  Ilo,  at  Arica,  and  in  the  neighborhood  of  Payta,  as  I  had  an  op- 
portunity of  ascertaining  during  my  stay  in  that  port.  The  inhab- 
itants of  Chinche  are  the  principal  traders  in  guano  ;  and  a  class  of 
small  vessels,  called  Guaneros,  are  constantly  engaged  in  carrying 
the  manure.* 

Fourcroy  and  Vauquelin  were  the  first  who  fixed  attention  on  the 
nature  of  guano.  The  specimen  which  they  examined  was  brought 
to  Europe  by  M.  de  Humboldt,  and  contained  :  Uric  acid  (0.25,)  ox- 
alate of  ammonia,  chlorhydrate  of  ammonia,  oxalate  of  potash, 
phosphates  of  potash  and  of  lime,  chloride  of  potassmrn,  fatty  matter, 
and  sand. 

Since  this  time  Dr.  Fownes  has  again  analyzed  guano.  The 
sample  upon  which  he  operated  was  of  a  light  brown  color  and  ex- 
tremely offensive  smell ;  it  yielded  : 


I 


Oxalate  of  ammonia 

Uric  acid 

Traces  of  carbonate  of  ammonia  and  organic  matter  ] 

Phosphates  of  lime  and  of  magnesia • 29.3 

Phosphates  and  alkaline  chlorides,  and  traces  of  sulphates 4.0 

100.0 


Another  sample,  deeper  in  color  and  without  smell,  contained  : 
Pure  oxalate  of  ammonia,  44.6;  earthy  phosphates,  41.2  ;  alkaline 
ohosphates,  sulphates,  and  chlorides,  14.2=100. 

The  composition  of  guano  would  confirm,  were  there  any  occasioa 

*  Humboldt,  Annales  deChimie,  vol.  Ivi.  p.  258. 
35 


290  NIGIIT-SOIL. 

for  confirmation,  the  opinion  that  has  beer,  formed  as  to  its  crigin. 
The  islets  which  supply  it  are  still  tenanted,  especially  during  the 
night,  by  a  multitude  of  sea-fowl.  Nevertheless,  from  the  calcula- 
tions of  M.  de  Humboldt,  the  excrements  of  these  birds  in  the  course 
of  three  centuries,  would  not  form  a  layer  of  guano  of  more  than 
one  third  of  an  inch  in  thickness  ; — imagination  stops  short,  startled, 
in  presence  of  the  vast  lapse  of  time  which  must  have  been  neces- 
sary to  accumulate  such  beds  of  the  substance  as  now  exist,  or 
rather,  as  lately  existed  in  many  places  ;  for  it  is  rapidly  disappear- 
ing since  it  has  become  a  subject  of  the  commercial  enterprise  of 
mankind.* 

The  average  composition  of  guano  must  by  no  means  be  inferred 
from  the  preceding  analyses  of  picked  samples  :  earthy  matters  are 
usually  present  in  much  larger  proportion  than  they  are  here  stated. 
The  guano  generally  imported  into  England  and  France  yields  a 
proportion  of  azote  very  far  short  of  that  which  the  25  per  cent,  of 
uric  acid  which  has  sometimes  been  stated  to  exist  in  this  substance 
would  yield.  In  three  trials  the  azote  found  was  0.14,  0.05,  and 
0.05  ;  the  mean  would  therefore  be  0.08,  which  represents  the  quan- 
tity of  azote  in  pigeon's  dung. 

The  litter  and  excrement  of  the  silkworm  is  used  as  manure  in 
the  south.     Analysis  indicates  3  per  cent,  of  azote  in  its  constitution. 

Human  excrements  are  regarded  as  one  of  the  most  active  ma- 
nures tliat  can  be  employed.  In  countries  where  agriculture  has 
made  real  progress,  this  article  is  highly  prized,  and  no  pains  are 
spared  to  obtain  so  powerful  a  manure.  In  Flanders,  feculent  mat- 
ters form  the  staple  of  an  active  traffic  ;  and  in  the  neighborhood  of 
large  towns,  they  form -an  invaluable  material  for  the  amelioration 
of  the  soil.  The  Chinese  collect  human  excrements  with  the  great- 
est solicitude,  vessels  being  placed  for  the  purpose  at  regular  dis- 
tances along  the  most  frequented  ways.  Old  men,  women  and  chil- 
dren, are  engaged  in  mixing  them  with  water,  which  is  applied  in 
the  neighborhood  of  the  plants  in  cultivation.!  The  fresh  excrement 
is  occasionally  worked  up  with  clay,  and  formed  into  bricks,  which 
are  pulverized  when  dry,  and  the  powder  is  applied  as  a  top-dress- 
ing. One  of  the  advantages  resulting  from  the  almost  exclusive 
use  of  this  manure  in  China  is  this,  that  the  fields  seem  to  grow 
nothing  but  the  plant  which  is  the  object  of  solicitude  with  the 
farmer ;  it  is  there  extremely  difficult  to  meet  with  a  weed.  The 
quality  of  feculent  matter  as  a  manure  depends  much  on  the  nature 
and  abundance  of  the  food  consumed  by  those  who  furnish  it.  M.: 
d'Arcet  relates  a  curious  anecdote  in  connection  with  this  fact :  a 
farmer  had  purchased  the  produce  of  the  cabinet  of  one  of  the  most 

*  Dr.  John  Davy,  all  whose  scientific  researches  equal  in  accuracy  the  brilHant  in 
vestigations  of  his  illustrious  brother,  has  lately  turned  his  attention  to  this  subject: 
he  finds  that  we  have  collections  of  guano  in  Great  Britain  that  are  really  not  to  ba 
despised  in  some  cases.  The  surface  of  the  ground  under  old-established  rookenes  is 
a  true  guano  bed ;  and  removed  and  used  as  manure  in  the  open  field,  produces  most 
excellent  effects.  See  Dr.  Davy's  paper  in  Ed.  Lend,  and  Dub.  PhUos.  Mag.  OcU  1, 
1844.— Eno.  Ed. 

t  Jollen,  Annates  de  Chimie,  vol.  Ui.  p.  65»  Sd  serlM 


WIGHT-SOIL.  291 

celebrated  restau/ateurs  or  taverns  of  the  Palais  Royal ;  encouraged 
by  the  success  he  obtained  in  employing  this  manure,  and  desirous 
of  obtaining  a  larger  supply  of  the  article,  he  rented  the  produce  of 
several  of  the  barracks  of  Paris.  The  manure  which  he  now  obtain- 
ed, hov/ever,  he  found  to  produce  an  effect  greatly  less  than  he  had 
anticipated,  so  that  he  lost  money  by  his  bargain.  Berzelius  found 
the  following  substances  in  human  excrements  : 

Remains  of  food 7.0 

BHe 0.9 

Albumen 0.9 

A  peculiar  extractive  matter 2.7 

Indeterminate  animal  matter,  viscous  matter, 

resin,  and  an  insoluble  residuum 14.0 

Salts  1.2 

Water 73.3 

100.0 

The  salts  had  the  composition  following : 

Carbonate  of  soda 29.4 

Chloride  of  sodium 23.5 

Sulphate  of  soda 11.8 

Ammoniaco-magnesian  phosphate • 11.8 

Phosphate  of  lime 23.5 

100.0 
Human  urine  is  one  of  the  most  powerful  of  all  manures.     Left 
to  itself  it  speedily  undergoes  putrefaction,  and  devolves  an  abun- 
dance of  ammoniacal  salts,  as  all  the  world  knows.     Its  composition, 
according  to  Berzelius,  is  the  following : 

Urea 3.01 

Uric  acid 0.10 

Indeterminate  animal  matter  >  ,  -, 

Laclic  acid,  and  lactate  of  ammonia  \    

Mucus  of  the  bladder 0-03 

Sulphate  of  potash 0.37 

Sulphate  of  soda 0.32 

Phosphate  of  soda , 0.29 

Chloride  of  sodium 0.45 

Phosphate  of  ammonia 0.17 

Chlorhydrate  of  ammonia 0.15 

Phosphate  of  lime  and  of  magnesia 0.10 

Silica traces 

Water 93-30 

100.00 

The  phosphates  of  lime  and  magnesia  which  it  contains  are  ex- 
tremely insoluble  salts,  and  have  been  supposed  to  be  held  in  solution 
by  phosphoric  acid,  lactic  acid,  and  very  recently  by  Professor 
Liebig,  by  hippuric  acid,  which  he  now  states  to  be  a  regular  con- 
stituent of  healthy  human  urine. 

From  the  interesting  inquiries  upon  urine  made  by  M.  Lecanu,  it 
appears  that  a  man  passes  nearly  half  an  ounce  of  azote  with  his 
urine  in  the  course  of  twenty-four  hours.  A  quantity  of  urine  taken 
from  a  public  urine  pail  of  Paris,  yielded  7  per  1000  of  azote.  The 
dry  extract  of  the  same  urine  yielded  nearly  17  per  cent. 

Human  soil  as  commonly  obtained  consists  of  a  mixture  of  fecu- 
lent matters  and  urine.     It  may  be  applied  immediately  to  the  ground 


292  FLEMISH  MANURE. 

as  it  eomes  from  the  privy.  In  some  parts  of  Tuscany  it  is  mixed 
with  three  times  its  bulk  of  water,  and  so  applied  to  the  surface.  I 
have  myself  seen  night-soil  as  it  was  obtained,  and  without  prepara- 
tion, spread  upon  a  field  of  wheat  without  any  ill  effect :  so  that  the 
Tuscan  preparation  may  be  regarded  as  a  simple  means  of  spread- 
ing a  limited  quantity  of  manure  over  a  given  extent  of  ground. 

It  is  in  French  Flanders,  however,  that  human  soil  is  collected 
with  especial  care  ;  it  ought  to  be  so  collected  everywhere.  The 
reservoir  for  its  preservation  ought  to  be  one  of  the  essential  articles 
in  every  farming  establishment,  as  it  is  in  Flanders,  where  there  is 
always  a  cistern  or  cess-pool  in  masonry,  with  an  arch  turned  over 
it  for  the  purpose  of  collecting  this  invaluable  manure.  The  bottom 
is  cemented  and  paved.  Two  openings  are  left :  one  in  the  middle 
of  the  turned  arch  for  the  introduction  of  the  material  ;  the  other, 
smaller  and  made  on  the  north  side,  is  for  the  admission  of  the  air, 
which  is  requisite  for  the  fermentation. 

The  Flemish  reservoir  may  be  of  the  dimensions  of  about  35 
cubical  yards.  Whenever  the  necessary  operations  of  the  farm  will 
permit,  the  carts  are  sent  off  to  the  neighboring  town  to  purchase 
night-soil,  which  is  then  discharged  into  the  reservoir,  where  it  usual- 
ly remains  for  several  months  before  being  carried  out  upon  the  land. 

This  favorite  Flemish  manure  is  applied  in  the  liquid  state  (mixed 
in  water)  before  or  after  the  seed  is  in  the  ground,  or  to  transplanted 
crops  after  they  have  been  dibbled  in.  Its  action  is  prompt  and 
energetic.  The  sowing  completed,  and  the  land  dressed  up  with  all 
the  pains  which  the  Flemish  farmer  appears  to  take  a  pleasure  in 
bestowing  upon  it,  a  charge  of  the  manure  is  carried  out  at  night  in 
tubs  or  barrels.  At  the  side  or  corner  of  the  field  there  is  a  vat  that 
will  hold  from  50  to  60  gallons,  into  which  the  load  is  discharged, 
and  from  which  a  workman,  armed  with  a  scoop  at  the  end  of  a 
handle  a  dozen  feet  in  length  or  more,  proceeds  to  lade  it  out  all 
around  him.  The  vat  emptied  in  one  place  is  removed  further  on, 
and  the  same  process  is  repeated  until  the  whole  field  is  watered.* 

The  purchase,  the  carriage,  and  the  application  of  this  Flemish 
manure  cannot  be  otherwise  than  costly  ;  we  therefore  see  it  given 
particularly  to  crops  which,  when  luxuriant  and  successful,  are  of  the 
highest  market  value — such  as  flax,  rape,  and  tobacco. 

This  manure,  the  sample  of  it,  at  least,  which  M.  Payen  and  I 
examined,  is  of  a  yellowish  green  color,  and  with  reference  to  smell 
cannot  be  compared  to  any  thing  belter  than  a  weak  solution  of 
hydrosulphate  of  ammonia.  This  salt  is  undoubtedly  present ;  but 
exposure  to  the  air  converts  it  rapidly  into  the  sulphate  of  the  same 
base.  According  to  M.  Kuhlmann,  the  quality  of  the  liquid  Flemish 
manure  is  to  be  judged  of  by  its  smell,  its  viscidity,  and  its  saline  and 
^harp  taste.  By  the  fermentation  which  takes  place  in  the  cess- 
pools, which  are  never  emptied  completely,  the  feculent  matter,  kept 
for  some  time  there,  does  in  fact  acquire  a  slight  viscidity.  When 
solid  excrementitious  matter  predominates  in  the  fermented  maaa 

*  Cordier,  Agriculture  of  French  Flanders,  p.  24a 


FLEMISH   MANURE.  293 

its  effect  upon  vegetation  is  of  longer  continuance  ;  but  when  it  is 
derived  entirely  from  urine,  it  acts  almost  immediately  after  its 
application.  In  either  case,  the  effect  of  Flemish  manure  does  not 
extend  beyond  the  season  ;  like  all  the  other  organic  substances  which 
have  undergone  complete  putrid  fermentation,  it  is  a  true  annual 
manure. 

Occasionally,  a  quantity  of  powdered  oil-cake  is  thrown  into  the 
reservoir.  This  is  either  when  the  manure  is  supposed  to  be  too 
dilute,  or  when  there  is  little  night-soil  at  command.  The  following, 
according  to  Professor  Kuhlmann,  is  an  example  of  the  employment 
of  the  Flemish  manure  in  a  rotation  which  is  common  in  the  neigh- 
borhood of  Lisle,  and  in  the  course  of  which  the  crops  are  colza  or 
colewort,  wheat  and  oats. 

First  year.  In  October  or  November,  the  land  is  manured  with 
farm-dung,  which  is  ploughed  in,  in  the  usual  way.  At  this  time 
a  dose  of  the  liquid  manure,  amounting  to  about  5000  gallons  per 
acre,  is  applied  :  a  second  ploughing  is  given,  and  the  colewort  is 
planted. 

Second  year.  The  colza  is  gathered,  the  ground  is  ploughed  for 
autumn  sowing ;  from  1000  to  1300  gallons  or  so  of  liquid  manure 
are  distributed,  and  the  wheat  is  sown. 

Third  year.  The  wheat  stubble  is  ploughed  down  at  the  end  of 
the  autumn,  and  about  1000  or  1100  gallons  of  the  liquid  manure 
per  acre  are  distributed  ;  the  oats  are  sown  in  the  spring.  If  cir- 
cumstances should  prevent  the  application  of  the  liquid  manure  in 
autumn,  it  is  laid  on  in  March,  and  then  it  has  been  found  that  one-fifth 
iCss  will  suffice  ;  but  its  application  at  this  season  is  avoided  as  much 
as  possible  on  account  of  the  havoc  that  is  made  by  the  passage  of 
horses,  carts,  and  men  over  the  surface  of  the  soft  ploughed  land.  It 
is  with  a  view  to  avoid  this  disturbance  of  the  surface  that  in  many 
places  oil-cake  in  powder  is  applied  to  the  fields  under  colza 
when  the  manuring  has  to  be  performed  after  the  crop  is  in  the 
ground. 

For  beet,  the  dose  of  Flemish  manure  is  carried  the  length  of  from 
1300  to  1400  gallons  per  acre  ;  but  when  the  root  is  intended  for  the 
manufacture  of  sugar,  liquid  manure  is  sedulously  avoided,  experience 
having  shown  that  it  has  the  very  worst  effect  upon  the  production 
of  sugar,  a  circumstance  which  is  very  easily  explained  upon  ground? 
that  have  already  been  given. 

The  price  of  Flemish  manure  at  Lisle  is  2^c?.  for  a  measure  con- 
taining 22  gallons.  In  Flanders,  it  is  held  that  this  quantity,  which 
will  weigh  hard  upon  2  cwt.,  is  equal  to  about  5  cwt.  of  farm-yard 
dung.  The  liquid  manure  which  I  analyzed  yielded  2  per  1000  of 
azote.  Farm-yard  dung,  in  its  usual  state,  contains  as  much  as  4 
per  1000 ;  it  follows,  therefore,  that  the  real  equivalent  number  of 
Flemish  manure  is  182,  that  of  farm  dung  being  100  ;  in  other  words, 
it  would  require  182  of  Flemish  manure  to  replace  100  of  farm-yard 
manure  ;  a  conclusion  that  differs  widely  from  that  which  is  usually 
acted  uporn.  But  it  must  be  observed  that  from  its  nature,  the  Flem- 
ish manure  produces  its  maximum  influence  in  the  course  of  the 

-5* 


294  POUDRETTE. 

season  in  which  it  is  applied.  It  seems  to  have  no  effect  oii  ihe 
crop  of  the  succeeding  year.  Farm-yard  dung,  on  the  contrary, 
only  exerts  a  portion  of  the  whole  amount  of  its  beneficial  influence 
in  the  course  of  the  year  in  which  it  is  laid  on  ;  it  has  still  something, 
often  much,  in  reserve  for  succeeding  years.  To  compare  liquid 
manure  with  farm-yard  dung,  with  reference  to  an  annual  crop,  is  to 
compare  this  manure  to  the  unknown  fraction  of  the  farm-yard  dung 
which  comes  into  play  in  the  course  of  the  first  year,  and  from  such 
a  contrast  no  possible  inference  can  be  drawn  in  regard  to  the  rela- 
tive value  of  the  two  kinds  of  dung.  1  have  insisted  upon  this  cir- 
cumstance, because  it  is  often  involved  in  the  estimates  that  are 
made  of  the  relative  values  of  the  different  species  of  manure  ;  and 
because,  from  losing  sight  of  it,  unfavorable  conclusions  are  frequently 
come  to  in  regard  to  manures  that  undergo  decomposition  very  slow- 
ly ;  these  manures,  nevertheless,  acting  for  a  great  length  of  time, 
produce  both  a  greater  amount  and  a  more  durable  kind  of  ameliora- 
tion of  the  soil.  Rapidity  of  action,  in  a  manure,  is  undoubtedly  a 
quality  that  is  highly  valuable  in  many  cases ;  and  Flemish  manure 
possesses  this  quality  in  the  highest  degree.  Nevertheless,  it  is  also 
an  advantage  to  possess  a  manure  which  elaborates  gradually,  and 
according  to  the  exigencies  of  vegetables,  those  principles  that 
contribute  to  their  growth,  and  which  suspend  in  a  great  measure 
this  elaboration  in  the  course  of  the  winter — which  remain  during 
the  cold  and  rainy  season  in  an  almost  inert  condition,  when  any 
fecundating  matter  produced  would  merely  be  washed  away  and  lost. 
These  advantages,  to  which  must  be  added  that  of  breaking  up  and 
lightening  the  soil,  are  all  possessed  by  good  farm-yard  manure. 
They  are  such,  in  fact,  that  this  manure,  even  in  Flanders,  is  still 
indispensable  ;  the  liquid  manures  of  that  country  are  nothing  more 
than  annual  auxiliaries. 

The  method  followed  in  Flanders  of  using  night-soil  is  certainly 
highly  rational ;  it  is  the  same  as  that  which  is  adopted  in  Alsace,  in 
the  neighborhood  of  towns,  with  this  difference,  that  our  farmers 
collect  no  store  of  the  material ;  they  go  in  quest  of  it  at  the  moment 
it  is  wanted.  It  is  applied  as  in  Flanders,  or  it  is  incorporated  with 
absorbent  substances,  such  as  straw,  or  with  other  more  consistent 
manures.  The  night-soil  of  Paris,  which  in  the  course  of  a  year 
amounts  to  an  immense  quantity,  is  treated  in  a  totally  different 
manner,  which  appears  to  be  in  opposition  to  the  simplest  notions  of 
science,  of  economy,  and  of  all  that  is  conducive  to  health.  I  allude 
to  the  mode  of  preparing  poudrette. 

In  the  neighborhood  of  Paris  there  are  places  appropriated  to  the 
reception  of  the  night-soil  :  it  is  thrown  into  reservoirs  of  no  great 
depth,  in  comparison  with  their  superficial  extent,  and  of  an  aggre- 
gate capacity  which  is  such  that  they  will  contain  the  whole  of  the 
products  collected  by  the  night-man  in  the  course  of  six  months. 
These  reservoirs  are  arranged  in  stages,  one  above  another.  Into 
the  upper  one  are  discharged  the  matters  collected  in  the  course  of 
the  night.  The  upper  reservoir  full,  a  slu'ce  is  opened  by  being 
pushed  partially  down,  which  allows  the  ir.rre  liquid  matters  to  es- 


POUDRETTE.  295 

cape  into  the  second  reservoir  placed  under  it.  Repeated  drainings 
are  effected  in  this  way,  and  when  the  second  basin  is  also  full,  there 
is  a  deposition  of  solid  matter  as  in  the  first ;  the  more  liquid  par- 
ticles are  then  let  off  from  the  second  into  the  third  reservoir,  and  so 
on  in  succession  until  the  last  and  lowest  is  attained,  from  which  the 
liquid  used  to  be  turned  into  a  watercourse  ;  but,  of  late,  these  con- 
taminated liquids  have  been  got  rid  of  by  means  of  what  may  be 
called  absorbing  artesian  shafts — deep  holes  pierced  in  a  dry  and 
porous  soil. 

When  the  deposite  in  the  first  reservoir  is  held  to  be  sufficiently 
consistent,  it  is  drained  by  lowering  the  sluicd  more  and  more ;  no 
fresh  matter  is  added,  the  new  charges  being  deposited  in  another 
system  of  reservoirs.  The  deposite  once  drained  is  in  the  pasty 
condition  ;  it  is  then  taken  out  with  the  spade,  and  spread  upon  au 
earthen  floor  which  slopes  off  on  either  side,  and  the  mass  is  turned 
from  time  to  time  to  favor  the  drying ;  this  process,  in  fact,  is  con- 
tinued until  the  material  has  become  pulverulent.  It  is  then  stored 
under  sheds,  or  thrown  up  into  pyramidal  heaps,  the  sides  of  which 
are  well  beaten  in  order  to  enable  them  to  throw  off  the  wet. 

Poudrette  is  of  a  brown  color,  and  weighs  nearly  150  lbs.  per 
sack.  Put  into  a  retort,  and  distilled  with  a  heat  of  from  424°  to 
930°  Fahr.,  it  yields  52.6  of  ammoniacal  fluid,  and  47.3  of  dry  mat- 
ter, in  which  we  encounter  fixed  ammoniacal  salts,  such  as  the  sul- 
phates, phosphates,  hydrochlorates,  &c.  M.  Jacquemart  finds  that 
in  100  parts  of  poudrette  there  is  1.26  of  ammonia,  the  greater  part 
in  the  state  of  carbonate  ;  but  it  contains  a  quantity  of  animal  matter 
besides,  which,  by  dry  distillation,  yields  a  nearly  equal  amount  of 
the  same  substance ;  whence  it  follows  that  poudrette  contains 
nearly  2^  per  cent,  of  volatile  alkali,  or  2  of  azote.  By  direct  analy- 
sis, I  obtained  1.6  of  azote. 

Poudrette  is  spread  upon  the  land  at  the  time  of  ploughing,  from 
26  to  34  bushels  per  acre  being  allowed.  On  meadow  lands  it  pro- 
duces very  good  effects  in  the  dose  of  about  25  bushels  per  acre. 
The  disgusting  smell  of  night-soil  is,  to  a  certain  extent,  an  obstacle 
to  its  general  use.  This  obstacle,  however,  is  only  felt  in  places 
where  agricultural  industry,  and  the  manufactures  connected  with  it, 
are  still  in  a  backward  state.  One  remarkable  circumstance  is,  that 
the  disgust  which  naturally  arises  from  the  manipulation  of  such  ar- 
ticles, has  been  more  especially  got  over  in  countries  that  are  justly 
celebrated  for  their  extreme  attention  to  cleanliness  and  the  easy 
position  of  their  inhabitants.  I  quote  Flanders  and  Alsace  in  proof 
of  the  fact.  It  has  been  said,  moreover,  that  certain  articles  pro- 
duced in  soils  manured  with  human  excrement  contract  a  smell  and 
taste  which  give  rather  unpleasant  information  of  the  nature  of  the 
manure  that  has  been  employed  to  favor  their  growth.  In  the  lim- 
ited circle  of  my  own  experience  on  this  subject,  I  can  say  that  I 
have  observed  nothing  which  favors  such  a  statement.  However 
this  may  be,  Mr.  Salmon  has  succeeded  in  disinfecting  night-soil 
completely,  by  mixing  it  with  a  kind  of  animal  charcoal  obtained  by 
calcining  in  close  vessels  a  porous  earth  impregnated  with  organic^ 


£96  COMPOSTS. 

substances.  This  is  the  article  which  is  sold  under  he  name  of 
animalized  black.  Its  quality  as  a  manure  must  depend  especially, 
I  might  even  say  entirely,  on  the  quantity  of  azotized  organic  matter 
which  enters  into  its  composition. 

Composts.  A  great  deal  has  been  written,  and  much  has  been 
Baid  on  the  advantages  of  composts,  or  mixtures,  contrived  with  a 
view  to  the  amelioration  of  the  soil.  The  receipts  for  these  com- 
posts are  very  numerous ;  they  prove  that  the  discovery  of  a  compost 
is  an  easy  matter,  and  requires  but  a  small  amount  of  ingenuity.  To 
unite  different  matters  in  such  a  way  as  to  obtain  a  compound  that 
shall  act  advantageously,  it  is  only  necessary  to  make  it  up  of  sub- 
stances which  of  themselves  and  isolatedl}^  are  good  manures.  But 
that  it  is  possible  to  supply  the  scarcity  of  manure,  to  create  it  in 
some  sort  by  means  of  composts,  is  a  subject  of  dispute.  In  fact, 
when  we  look  attentively  at  the  numerous  mixtures  which  have  been 
indicated  as  leading  to  this  end,  we  always  perceive  that  the  propo- 
sal amounts  to  an  extension  or  dilution  of  some  powerful  manure 
with  a  substance  that  is  either  inert  or  has  little  activity.  This  mode 
of  proceeding  may  have  its  advantages;  it  enables  us  to  make  a 
more  equal  distribution  of  the  manure  we  have  at  our  disposal,  but 
it  actually  supplies  us  with  none. 

Earthy  substances  almost  always  figure  in  composts.  Turf-ashes, 
wood-ashes,  marl,  and  particularly  lime,  are  constant  ingredients. 
Marl  may  suit  certain  soils ;  lime  is  a  substance  of  great  activity, 
and  which  for  this  reason  must  be  admitted  into  composts  with  cau- 
tion ;  it  may  act  in  the  disintegration  of  woody  parts — of  stalks,  and 
stems,  and  leaves ;  but  we  must  be  very  careful  not  to  follow  the 
recommendation  of  Schwertz,  who  would  have  us  throw  quick-lime 
into  our  privies  with  the  view  to  bringing  the  matters  there  contained 
into  a  consistent  and  readily  pulverizable  state.  By  doing  so  we 
should  infallibly  lose  the  greater  part  of  the  principles  that  are  truly 
useful  in  the  soil.  Much  mischief  and  great  destruction  of  manure, 
indeed,  have  been  the  consequence  of  the  insensate  and  indiscrimi- 
nate use  of  quick-lime  under  all  circumstances ;  the  business  is 
much  rather  to  preserve  than  to  destroy  the  substances  that  are  used 
as  manures  ;  the  purpose  is  to  fix,  not  to  dissipate  the  volatile  elements 
which  they  contain.  One  great  objection  to  the  extensive  employ- 
ment of  composts  is  the  amount  of  labor  they  require  in  the  repeated 
turnings  which  are  held  necessary  in  their  preparation,  and  in  the 
large  quantity  of  matter  which  has  to  be  transported. 

The  following  table  will  be  found  iseful  as  giving  a  comprehen- 
sive view  of  the  proportion  of  azote  ;ontained  in  the  various  kinds 
of  manures  which  have  been  partic  ilarly  examined,  and  of  their 
equivalents,  referred  to  farm-yard  du;  g  as  the  standard. 


MANTJRES. 


297 


TABLE  OF  THE  COMPARATIVE  VALUE  OF  MANURES 

DEDUCED  FROM  ANALYSES  MADE  BY  MESSRS.  PAYEN  AND  BOUSSINGAULT. 


1 

Azote  in 

Quality  ac- 

Equivalent 

100  of  matter. 

cording    to 
state. 

according  to 
state. 

Kind  of  Dung. 

p. 

Remarks. 

s 

1 

Dry. 

Wet. 

Dry. 

Wet. 

Dry. 

Wet. 

Farm.yar(i  dung  .    . 
Dung  from  an  inn  yard 

79.3 

1.95 

0.41 

100 

100 

1R9 

100 

Aver,  of  Bechelbronn. 

60.6 

2.08 

0.79 

107 

107 

94 

51 

From  south  of  France. 

Dung  wiiter .... 

99.6 

1.54 

0.06 

78 

2 

127 

68 

Washed  by  the  rain. 
Fresh,  of  Alsace.  1838. 

Wheat  straw    .    .    . 

19.3 

0.30 

0.24- 

15 

60 

^ 

167 

Idem 

5.3 

0.53 

0.49 

27 

122.5 

367 

82 

Old  Irom  environs  ol 

Paris. 
Ditto  stubble. 

Idem 

5.3 

?-^§ 

0.41 

22 

102.5 

fi 

98 

Idem 

9.4 

L42 

L33 

73 

332.5 

137 

30 

Ditto  upper  part,  ear 
included. 

&^*""  :  :  :  : 

12.2 

0.20 

0.17 

10 

42.5 

975 

235 

Of  Alsace, 

0.50 

0.42 

26 

105 

390 

95 

Environs  of  Paris,  1841. 

Oat  straw     .... 

21  0 

0.36 

0.28 

18 

70 

542 

143 

■i 

Barley  straw     .    .    . 

n.'o 

0.26 

0.23 

13 

57.5 

750 

174 

1 

Wheat  chaff    .    .    . 

l-^ 

0.94 

0.85 

48 

212.5 

207 

E 

i  pf  Alsace. 

Pea  straw     .... 

8.5 

1.95 

1.79 

100 

447.5 

199 

22 

1 

Millet  straw      .    .    . 

19.0 

0.96 

0.78 

49 

195 

203 

ii 

j 

Buckwheat  straw     . 

11.6 

0.54 

0.48 

27 

120 

361 

83 

Lentil  straw      .    .    .' 

9.2 

^•^ 

1.01 

57 

2cO 

^^ 

40 

Dried  potato  tops      . 

12.9 

0.43 

0.37 

92.5 

453 

108 

Withered  madia  stalks 

14.3 

0.66 

0.57 

33 

142.5 

295 

70 

After  seeding. 

Idem     turned    under 

while  green        .    . 

70.6 

1.53 

0.45 

79 

113 

126 

89 

Before  seeding. 

Dried  broom     .    .    . 

10.4 

1.37 

1.22 

70 

305 

142 

33 

Stalk  and  leaves. 

Withered    leaves    of 

beet-root   .... 

88.9 

4.50 

0.50 

230 

125 

43 

80 

Of  mangel  wurzel. 
Wither*d  top  &  leaves. 

Ditto  of  potatoes  .    . 

76.0 

2.30 

0.55 

117 

137.5 

85 

73 

Ditto  of  carrots     .    . 

70.9 

2.94 

0.85 

150 

212.5 

66 

47 

Leaves  of  heather 

7.0 

i-is 

1.74 

103 

23 

Dried  in  the  air. 

Ditto  of  pear-trees     . 

14.5 

1.59 

1.36 

81  5 

340 

127 

29 

Ditto  of  oak     .    .    . 

25.0 

1.57 

1.18 

80" 

293 

125 

34 

1 

Ditto  of  poplar      .    . 
Ditto  of  beech  .    .    . 

51,1 

1.17 

0.54 

66 

134 

167 

^4 

I  Leaves  fallen  in  au- 

39.3 

1.91 

1.18 

78 

294 

102 

34 

1      tumn. 

Ditto  of  acacia     .    . 

53.6 

1.56 

0.72 

80 

180 

125 

56 

J 

Box-tree 

59.3 

2.89 

1.17 

147 

293 

68 

34 

Branches  and  leaves. 

Barred  clover-roots  . 

9.7 

1.77 

1.61 

90 

402.5 

110 

25 

Dried  in  the  air. 

Fucus  digitatus    .    . 

1.41 

72 

215 

139 

46 

) 

Idem 

4o;o 

1.58 

0.95 

81 

123 

^ 

>  Dried  in  the  air. 

Fucus  saccharinus    . 

40.0 

2.29 

1.38 

117 

345 

85 

29 

i 

Idem 

75.5 

0.54 

135 

74 

Fresh. 

Burnt  sea-weed     .    . 

3.8 

6.40 

0.38 

20 

95 

488 

JS5 

Oyster  shells     .    .    . 

17.9 

0.40 

0.32 

20 

80 

488 

125 

Sea  shells     .... 

0.05 

0.05 

3 

13 

3750 

769 

Dried    sea    shelL«    of 
Dunkirk. 

Mud  of  the  Morlaix 

river 

Trez  of  Roscoff  roads 

3.7 
0.5 

0.42 
0.14 

0.40 
0.13 

'i 

100 

464 

100 
308 

\  Sea  sand. 

Sea-side  marl   .    .    . 

1.0 

0.52 

0.51 

26.5 

128 

^Z 

'5 

Salt  cod-fish      .    . 

38.0 

10.86 

6.70 

557 

1675 

18 

6 

Cod-fish  washed   and 

pressed      .... 

Fir  saw-dust     .    .    . 

10.0 

18.74 

16.86 

961 

4215 

10 

o-P 

Dried  in  the  air. 

24.0 

0.22 

0.16 

11 

40 

886 

250. 

}            ... 

Idem 

24.0 

0.31 

0.28 

15 

57.5 

629 

174 

5  Dried  in  the  air. 

Oak  saw-dust  .    .    . 

26.0 

0.72 

0.54 

36 

135 

256 

74 

i 

White  lupine  seed     . 
Malt  grains  .... 

II 

3.49 
4.51 

872.5 
1127.5 

S 

nii 

Tuscan,  boiled  &  dncd 

Grape  husks     .    .    . 

3.31 

1.71 

169 

M^ 

57 

23 

Oil-cake  of  linseed    . 

13  4 

6.00 

5.20 

307 

l.SOO 

33 

8 

Ditto  of  colewort  .    . 

10.5 

5.50 

4.92 

^2 

1230 

35 

8 

Ditto  of  Arachis   .    . 

6.6 

8.89 

8.33 

655 

2082  5 

21 

1^ 

Ditto  of  madia      .    . 

11.1 

5.70 

5.06 

292 

1265 

^ 

8 

Ditto  of  sesame     ,    . 

6.5 

5.93 

5.52 

304 

1378 

^ 

71 

Oil-cake  of  hempseed 

5.0 

4.78 

^ 

1052 

41 

& 

Ditto  of  poppy      .    , 
Ditto  of  beech  mast  . 

6.0 

5.70 

5.36 

292 

1340 

34 

7 

6.2 

3  31 

181 

828 

55 

^f 

Ditto  of  walnuts  .    . 
Ditto  of  cotton  seed  . 

6.0 

5  59 

5-^ 

^I 

1310 

35 

3 

11.0 

4.52 

4.02 

231 

1000 

^ 

10 

098 


MAI4UBES. 


g 

.»^"Si.  -b:- 

Equivalent 

"^ 

I 

according  to 
state. 

KindofDunf. 

temarki. 

1 
1 

Dry. 

Wet. 

Dry. 

Wet. 

Dry. 

Wet. 

Ditto  from  refiners    . 

10.0 

3.92 

8.54 

201 

885 

50 

m 

Recent  fat  by  means 
of  poplar  sawdust. 

Ditto  ditto    .... 

7.7 

0.58 

M 

30 

135 

332 

75 

Fish  oil  by  ditto  ditto. 
Dried  in  the  air. 

Cider-apple  refuse    . 

r,^-^ 

0.63 

^•^ 

32 

147 

309 

^ 

Refuse  ofliops      .    . 
Beet-root  refuse     .    . 

73.0 

2.23 

0.56 

114 

140 

88 

67 

9.3 

1.26 

1.14 

64 

285 

155 

35 

Dried  in  the  air. 

Idem 

70.0 

0.38 

64 

85 

106 

Fresh  from  the  press. 
Process  of  Dombasle. 

Squeezed  beet-root   . 

1.76 

O.Ol 

90 

2 

lii 

4137 

Potato  refuse    .    .    . 

73.0 

1.95 

0.53 

100 

131.5 

100 

76 

Potato  juice      .    .    . 

95.4 

8.28 

0.38 

425 

94 

23 

106 

Settled  and  decanted. 

Water  of  the  starch 

- 

manufactory      .    . 

.99.2 

8.28 

0.07 

425 

17.5 

571 

From  washing  in  four 

Deposite  from  the  wa- 

volumes of  water. 

ter  of  ditto     .    .    . 

80. 

1.81 

0.36 

92 

90. 

108    1  111 

Drainings  from  heap. 

Idem 

15. 

1.81 

L54 

92 

384.5 

..    1    24 

Dried  in  the  air. 

Solid  cow-dung    .    . 
Urine  of  cows  .    .    . 

85.9 

2.30 

0.32 

117 

80 

84 

125 

3.80 

0.44 

194 

110 

51 

91 

Mixed  cow-dung  .    . 

84  3 

2.59 

0.41 

132 

102.5 

75 

98 

Solid  horse-dung  .    . 
Horse  urine  .... 

75^3 

2.21 

0.55 

113 

137.5 

88 

73 

79.1 

12.50 

2.61 

6^1 

652.5 

15i 

ISA 

The  horse  drank  but 

Alixed  horse-dung     . 

75.4 

3.02 

0.74 

154 

185 

66    1    54 

little ;  the  urine  was 

Pig-dung      .... 

81.4 

3.37 

0.63 

172 

157.5 

58 

63 

thick. 

Sheep-dung      ,    .    . 

63.0 

2.99 

1.11 

153 

277.5 

65 

36, 

(ioal-dung    .... 

46.0 

3.93 

2.16 

201 

540 

50 

18i 

Liquid  Flem.  manure 

Sl^ 

47.5 

210 

In  the  normal  state. 

[deiH 

0.22 

55 

, , 

182, 

PoudretteofBelloni. 

12.5 

4.40 

3.85 

225 

44 

loi 

Dried  in  the  air. 

Ditto  of  Montfaucon 

41.4 

2.67 

1.56 

137 

390 

73 

% 

Urine  of  public  vats . 

96. 

17.56 

16.83 

900 

4213 

1 

Dried  in  the  stove. 

Idem    ...... 

96.9 

23.11 

0.72 

1133 

179 

Sk 

56 

Thin,  ammoniacal. 

Animalized  black     . 
Idem  from  the  neigh- 
borhood of  Paris    . 

44.6 

1.96 

1.09 

100.5 

272 

98 

37 

Prepared  for  11  mouths 

42.0 

2.96 

1.24 

151.6 

310.5 

66 

32 

Recently  made. 

Idem,     called    Dutch 
manure     .... 

44.1 

^•^ 

1.36 

127 

340 

79 

i 

Made  at  Lyons. 

Animalized  sea. weed 

12.1 

2.73 

2.40 

140 

600 

7 

Dried  in  stove,  (from 

Marseilles.) 
OfBechelbronn. 

Pigeon's  dung     .    . 

9.6 

9.02 

8.30 

462 

2075 

21i 

5 

Guano  imported  into 
England    .... 

19.6 

6.20 

5.00 

323 

1247 

3U 

80 

In  the  ordinary  state. 

Idem 

23.4 

7.05 

5.40 

361 

1349 

28^ 

74 

Sifted. 

Do.  imp.  into  France 

1L3 

15.73 

13.95 

807 

3487 

12i 

28i 

Silk-worm  litter   .    . 

14.3 

3.48 

3.29 

178.7 

827 

56 

12 

Fifth  age. 

Idem 

11.4 

3.71 

3  29 

190 

822 

53 

12 

Sixth  age. 

Chrysalis  of  silk-worm 

78.5 

8.99 

1:95 

461 

485 

21i 

20J 

(Jockchafers      .    .    . 

77.0 

13.93 

3.20 

714 

801 

14 

13 

Dried  muscular  flesh 

8.5 

14.25 

13.04 

730 

3260 

111 

3, 

Dried  in  the  air. 

Soluble  dried  blood  . 

21.4 

15.50 

12.18 

795 

3i 

As  sold. 

Liquid  blood    .    .    . 

81.0 

2.95 

795 

736 

13i 

From  slaughterhouses. 

Idem    ...... 

82.5 

2.71 

795 

580 

15' 

From  worn-out  horses. 

Blood  coagulated  and 
pressed 

78.5 

17.00 

4.51 

871 

1128 

111 

9, 

Just  out  of  the  press. 

Insoluble  dried  blood 

12.5 

17.00 

14.88 

871 

3719 

2i 

Dried  in  manufactory. 

blue  manufactory  . 

53.4 

2.80 

1.31 

144 

526 

7 

30i 

Animalized  with  blood 

Meiter's  bones  .    .    , 

7.5 

7.58 

7.02 

388 

26 

6 

Dried  in  the  air. 

Fresh  bones .... 

30.0 

5.31 

1326 

* 

7^ 

As  sold  by  the  melters. 

Fat  bones,  not  heated 

8.0 

1554 

64 

Including  0.10  of  fat. 

Dregs  of  bone  g».ue    . 
Glue  dregs    .... 

t§ 

0.91 
5.63 

0!53 
3.73 

A, 

& 

^y 

76 
11, 

As  sold  by  the  makers. 

Graves 

8.2 

12.93 

11.88 

663 

296953 

15 

3i 

Animal  black  of  the 

sugar  refiners     .    . 

47.7 

2.04 

1.06 

104 

265 

96 

38 

As  sent  out. 

Sugar  refiner's  black 

27.7 

19.01 

13.75 

974 

3437 

103 

28 

From  Paris. 

From  the  sugar  bakery 

Scutn  from  the  sugar 

Enllish'^lack  !    '.    '. 

67.0 

1.58 

0.54 

81 

134 

127 

75 

of  Vigneux. 
Blood,  lime,  soot 

13.5 

8.02 

6.95 

411.4 

1738 

24 

6 

Feathers 

12.9 

17  61 

15.34 

903 

11 

H 

Cow-hair  flock     .    . 

8.9 

15.12  1  13.78 

775 

3445 

13. 

3 

Woollen  rags    .    .    . 

11.3 

20.26    17.98 

1039 

4495 

,1 

n 

Horn  shavings  .    .    . 

9.0 

15.78    14.36 

809 

3590 

3 

Coal  soot      .... 

15.6 

1.59     I.a5 

81 

337.5 

30 

Wood  soot   .... 

5.6 

1.31      1.15 

67 

287.5 

149 

35 

Picardy  ashes  .    .    . 

9.2 

0.71  i    0.65 

96 

162.5 

275 

62 

Veget.  mould  from  bn- 
1    mus  dnng  (terreaii) 

•  •    1 

1.03 

.. 

53 

10 

33 

Dried  in  the  stove. 

MANURES.  299 

It  is  almost  unnecessary  to  give  any  explanation  of  the  uses  that 
may  be  made  of  the  preceding  table  :  I  shall,  however,  give  a  few  il- 
lustrations from  instances  which  have  actually  occurred  in  my  ex- 
perience. 

Oil-caka  is  cheap  at  this  time,  (1842  ;)  and  the  question  is,  whether 
it  couM  be  advantageously  employed  in  connection  with  the  culti- 
vation of  wheat.  The  presumption  is,  that  wheat  obtains  the  whole 
of  its  azote  in  the  soil,  that  it  acquires  none  from  the  atmosphere  ; 
and  again,  I  assume  that  the  whole  of  the  azote  put  into  the  ground 
would  be  used  up  by  the  crop.  Under  the  most  favorable  circum- 
stances of  heat  and  moisture,  this  would  probably  be  the  case  ;  were 
it  not  so  to  the  letter,  the  active  matter  which  remained  in  the 
ground  would  operate  advantageously  in  succeeding  years.  The 
following,  then,  are  the  elements  of  the  question : 

1st.  In  the  wheat  grown  at  Bechelbronn  there  is  on  an  average 
0.025  of  azote.  2d.  In  the  straw  of  1841, 1  have  just  found  0.003 
of  azote.  3d.  The  oil-cake  which  I  propose  to  employ  coi.lains 
0.055  of  azote,  and  its  actual  price,  crushing  included,  is  3.?.  4c?.  per 
cwt.  4th.  The  relation  in  point  of  weight  of  the  grain  to  the  straw 
is  as  47  :  100. 

A  sheaf  or  bundle  of  wheat,  220  lbs.  in  weight,  consists  of: 

Wheat  70.4  lbs.,  containing  1.760  of  azote,  and  is  worth 4*.  8d. 

Straw  149.6  lbs.  "         0.415  "  "  Is.  8d. 

Total  of  azote 2.175  Total  value 6s.  4d. 

Difference  of  value 5s.  4d. 

To  grovir  which,  39  lbs.  of  oil-cake  would  be  required,  of  the 
value  of. Is.  2d. 

So  that  39  lbs.  of  oil-cake,  converted  into  a  sheaf  of  wheat,  would 
be  increased  in  intrinsic  value  to  the  extent  of  5;?.  2d.  Supposing 
that  but  one-half  or  one-third  of  this  amount,  as  indicated  by  theory, 
is  realized  in  practice,  it  is  obvious  that  the  addition  of  the  oil-cake 
might  be  made  with  advantage ;  and  that  no  means  should  be 
neglected  to  ensure  the  success  of  its  application  as  a  manure.* 

The  production  of  oil-cake  in  France,  the  Netherlands,  and  other 
countries  of  Europe,  is  very  considerable ;  in  round  numbers,  100 
of  oleaginous  seeds  yield  60  of  cake ;  but  it  has  been  calculated, 
with  rare  ability,  and  from  authentic  documents,  by  M.  Leroy  de 
Bethune,  that  not  only  is  the  whole  of  the  oil-cake,  which  is  the 
produce  of  the  soil  of  France,  exported,  but  that  likewise  of  the 
oleaginous  seeds  which  she  imports  from  other  countries.  This  M. 
de  Bethune  looks  upon  as  a  very  lamentable  agricultural  fact.  I 
have  shown,  indeed,  from  the  example  which  I  have  quoted,  that 
every  pound  of  cake  represents  a  primary  material,  which,  properly 
treated,  may  be  transformed  into  nearly  6  pounds  weight  of  wheat- 
grain  and  straw,  having  a  value  infinitely  greater  than  that  of  the 
oil-cake  originally  employed. 

*  Our  author  has  of  course  left  many  other  elements  very  necessary  to  be  included 
out  of  his  calcW'Uion  here,  such  as  labor,  seed,  rent  charge,  interest  on  capital,  *• 
fiKo.  Ed. 


SOO  EXPORTATION    :  F    MANURES. 

While  I  agree  with  M.  de  Bethu:  e,  that  it  is  generally  wibe  to 
encourage  exportation,  I  also  admit  with  him  that  there  are  sub- 
stances in  reference  to  which  it  wot  Id  be  prudent  to  discourage  ex- 
portation ;  oil-cake,  this  powerful  rjeans  of  giving  fertility  to  the 
soil,  might  be  placed  in  the  foremost  rank  of  such  substances.  I  am 
far  from  adopting  all  the  principles  of  economists,  which  appear  to 
me  to  be  frequently  far  too  absolute.  In  my  opinion,  any  exportation, 
the  consequence  of  which  is  the  impoverishment  of  the  soil,  ought 
to  be  prohibited.  I  should,  for  instance,  oppose  the  exportation  of 
arable  soil  ;  and  in  the  same  way,  to  allow  an  active  manure  to  pass 
into  the  hands  of  strangers,  is,  in  my  eyes,  tantamount  to  exporting 
the  vegetable  soil  of  our  fields,  to  lessening  their  productiveness,  to 
raising  the  price  of  the  food  of  the  poor ;  for  as  much  labor  is  re- 
quired, as  much  care  and  capital  must  be  expended  upon  an  ungrate- 
ful soil  to  obtain  a  little,  as  upon  a  fertile  soil  to  procure  an  ample 
return.  To  permit  the  exportation  of  oil-cake  is  to  hinder  the  hus- 
bandman from  taking  advantage  of  all  the  circumstances  with  which 
nature  presents  him  ;  it  is  as  if  a  chill  were  to  be  brought  over  the 
genial  climate  of  France.* 

I  have  shown  the  advantages  of  the  application  of  oil-cake  in  the 
growth  of  wheat.  I  shall  now  inquire  whether  or  not  it  is  equally 
useful  in  connection  with  hay  and  potato  crops ;  the  price  of  the 
article  being  presumed  to  be  the  same  as  before. 

Upland  meadows,  when  they  have  not  been  soiled,  yield  miserable 
returns,  and  their  situation  renders  them  difficult  of  access  to  carts  : 
oil-cake  in  such  circumstances  comes  powerfully  to  our  aid. 

Taking  the  price  of  hay  at  5s.  per  220  lbs,,  which  is  about  its 
present  price  in  France,  and  taking  into  account  the  composition  of 
the  after-math,  we  may  reckon  the-  azote  contained  in  the  hay  of 
natural  meadows  at  0.015. 

220  lbs.  of  hay,  containing  3  lbs.  of  azote,  will  be  worth 5«.  Od, 

To  produce  which  56  lbs.  of  cake  (azote  3.3  lbs.)  worth Is,  8d. 

would  be  required.  

Difference  in  value  between  the  cost  and  the  crop 3s.  4d. 

Upon  this  showing,  oil-cake  may  be  advantageously  employed  in 
the  amelioration  of  upland  meadows.  Besides  the  cost  of  the  ma- 
nure, however,  there  are  the  very  necessary  additions  to  be  made  of 
the  price  of  labor  and  rent. 

From  the  observations  which  I  made  at  Bechelbronn  in  1839,  I 

*  I  own  I  am  surprised  at  this  passage  in  my  esteemed  author.  There  is  nothing 
parallel  in  the  instances  he  quotes.  Did  not  the  French  husbandmen  and  oil-pressors 
jn-ofit  by  the  exportation  of  oil-cake  they  woBld  keep  it  at  home  ;  and  the  profit  of  the 
farmer  and  manufacturer  is  the  profit  of  the  whole  coiimiuriity.  To  export  the  soi: 
would  indeed  be  madness :  it  would  obviously  be  killinji  the  goose  that  lays  the  goldea 
eggs  ;  but  to  export  that  which  the  soil  produces  in  abundance  year  after  year,  is  a 
totally  diflferent  affair,  M.  Boussingault's  reasoning  would  lead  the  wine-growers  of 
Bordeaux  and  Burgundy  to  refuse  us  a  hogshead  of  their  smallest  growth  :  they  cannot 
send  it  to  vs  without  impoverishing  their  sul,  any  more  than  they  can  let  us  have  a  pound 
of  their  oil-cake.  But  one  half  of  the  vegetables  tliat  grow,  at  least,  are  at  work  ac- 
cumulating the  materials  from  the  atmosphere  and  water,  out  of  which  the  other  half 
are  supplied,  and  so  the  process  of  wnste  fmd  tnpply,  of  destruction  and  reproducUoo, 
goes  on  wiih'jul  limit;-,  and  wiihcut  cnd.-^E.NQ.  Ed. 


USE  OF  THE  PRECEDING  TABLE.  301 

find  that  the  relation  between  the  weight  of  potatoes  as  they  come 
from  the  ground,  and  that  of  the  tops  or  haum,  supposed  to  be  dry, 
is  as  100  is  to  6.4. 

The  tubers  contain : 
Azote  0.0036  per  10000  parts ;  and  220  lbs.  contain  0.729  of  a  lb.  of 

azote,  and  are  worth Is.  8d. 

The  tops  or  haum,  dry,  contain : 
Azote  0.0230  per  10000  parts ;  and  14  lbs.  contain  0.330  of  a  pound 

of  azote. 
Total  of  azote  1.122. 
Now  20.4  lbs.  of  cake  which  would  be  required  to  produce  220 

lbs.  of  potatoes,  contain  1.1  lb.  of  azote,  and  are  worth 0«.  lid. 

Difference ..Is.  Oid.. 

The  oil-cake  at  the  price  of  3*.  2d.  per  cwt.  may  therefore  be  ad- 
vantageously used  for  the  production  of  potatoes  :  rent,  labor,  seed, 
&c.,  considered  as  before.  At  the  price  of  7s.  6d.  or  8^.  6d.  per 
cwt.,  however,  to  which  oil-cake  occasionally  rises,  it  would  not  be 
possible  to  employ  it  profitably  in  this  way.  The  cost  of  the  manure 
would  then  amount  to  nearly  as  much  as  the  value  of  the  crop. 

The  equivalent  numbers  in  the  table  express  the  relative  values 
of  different  manures ;  they  proclaim  the  proportions  in  which  one 
substance  must  be  substituted  for  another,  and  when  purchases  are 
to  be  made,  they  will  show  at  a  glance  which  is  the  article  that  is 
really,  and  in  fact,  the  cheapest.  The  equivalent  number  of  one 
variety  of  oil-cake,  for  instance,  is  7.25  ;  that  of  farm-yard  dung  is 
100  ;  which  is  as  much  as  to  say  that  in  reference  to  mere  fertilizing 
elements,  100  parts — lbs.  cwts.  or  tons,  of  farm-yard  dung  may  be 
replaced  by  7^  parts — lbs.  cwts.  or  tons  of  oil-cake ; — 2  cwt.  of 
farm-dung,  for  instance,  by  14|^  lbs.  of  cake.  The  2  cwt.  of  farm- 
dung  is  valued  in  the  table  at  6d.,  or  about  5s.  per  ton  ;  the  14|  lbs. 
of  cake  would  cost  5^d.  It  is  obvious,  therefore,  that  even  at  the 
above  low  price  of  oil-cake,  there  would  be  no  real  advantage  in 
substituting  it  generally  for  farm-yard  dung  ;  in  situations,  however, 
remote  from  large  towns,  where  it  is  almost  impossible  to  procure 
dung,  or  where  the  carriage  of  large  masses  of  dung  would  be  both 
difficult  and  expensive,  there  would  then  be  advantage  in  the  sub- 
stitution. 

Woollen  rags  at  the  price  of  about  2*.  10c?.  per  cwt.  are  more  pro- 
fitable than  farm-yard  dung  at  3^.  per  cwt.  The  equivalent  of  the 
rags  is  2.22,  and  this  quantity  (2.22  lbs.  avoird.)  of  rags  is  worth 
about  ^d.  ;  by  the  substitution  of  the  rags  for  farm-yard  manure, 
therefore,  a  saving  is  effected  of  about  2|<i.  on  every  cwt.  of  the 
latter  that  must  have  been  employed.  In  good  farming,  however, 
it  is  less  with  reference  to  the  money  advantage  of  substituting  one 
manure  for  another,  that  calculations  are  made,  than  with  reference 
to  the  possibility  of  procuring  either  one  manure  or  another  at  a 
moderate  price.  The  estimated  value  of  the  dung  in  one  of  the 
columns  of  the  table  gives  us  at  once  the  price  that  may  be  paid  for 
it ;  for  this  purpose  it  is  enough  to  know  the  value  of  standard  dung  : 
let  this  be  as  it  usually  is,  3^.  per  cwt. ;  if  we  would  now  know 
what  maj  be  paid  for  a  hundred  weight  of  bones  simply  ('ried  in  th« 

26 


802  VALUE    OF    DIFFERENT    MANURES. 

air,  the  number  designating  these  being  1554,  we  have  only  to  make 
a  simple  equation  in  the  following  terms  : — 100  :  3d.  :  :  1554  :  a,  to 
have  the  solution  :  =3s.  lOhd. 

The  most  careful  consideration  of  the  relative  value  of  different 
manures  under  th^  guidance  of  the  analytical  elements  which  I  have 
indicated,  justifies  the  preference  which  is  given  in  practice  to  one 
kind  over  another,  which  on  simple  examination  appears  to  offer 
greater  advantages.  Thus,  by  diffusing  oil-cake  through  water,  and 
leaving  the  mixture  to  ferment,  a  manure  is  obtained  which  presents 
all  the  characters,  which  possesses  all  the  properties  of  human  soil 
that  has  undergone  fermentation  in  privies  or  cess-pools.  And  it  is 
to  this  mixture  of  putrid  oil-cake  that  the  husbandmen  of  French 
Flanders  have  recourse,  as  we  have  seen,  when  their  supply  of 
night-soil  runs  short.  When  oil-cake  is  low  in  price,  say  about  3^. 
3d.  or  35.  4d.  per  cwt.,  it  might  seem  advantageous  to  manufacture 
Flemish  manure  with  it ;  expensive  carriage  and  time  would  be 
saved  ;  for  night-soil  has  generally  to  be  fetched  from  a  distance, 
and  containing  but  0.002  (y/o  o^hs)  of  azote,  it  is  bulky,  and  its  equiv- 
alent is  in  the  same  proportion  high.  Cameline  oil-cake  contains 
0.055  (ylf^ths)  of  azote  ;  to  make  Flemish  manure  that  should  con- 
tain 0.002  of  azote,  it  would  be  requisite  to  add  to  every  100  parts 
of  cake  2,650  parts  of  water  ;  the  cwt.  of  this  manure  would  then 
come  to  l^d.,  while  Flemish  manure  prepared  with  night-soil,  would 
cost  the  farmer  but  l^d.  I  have  here  taken  the  cake  at  a  tow  price; 
were  it  7^.  6d.  per  cwt.  instead  of  3*.  9d.,  which  is  perhaps  much 
nearer  its  usual  average  cost,  it  is  obvious  that  the  cwt.  of  manure 
prepared  from  it,  would  cost  twice  as  much  more. 

The  proportion  of  azote,  the  value,  and  the  equivalents  of  the 
several  manures  are  given  in  the  table,  both  for  the  substances  ab- 
solutely dry,  and  for  the  condition  in  which  they  are  commonly  em- 
ployed. This  distinction  is  one  of  great  importance.  The  water, 
the  quantity  of  which  is  indicated  in  the  first  column,  is  a  most 
variable  constituent ;  its  presence,  of  course,  depreciates  the  ma- 
nure in  the  precise  ratio  in  which  it  occurs.  The  reference  of  all 
the  elements  of  each  particular  manure  to  that  manure  in  a  state  of 
absolute  dryness,  is  a  very  important  feature  in  the  table.  In  pur- 
chasing manures,  the  precaution  of  drying  them  chemically  must 
never  be  neglected,  more  especially  in  connection  with  articles, 
which  by  their  nature  are  capable  of  absorbing  water  in  consider- 
able, and  often  in  very  different,  quantities. 


LIMING.  303 


CHAPTER  VI. 

OF    MINERAL    MANURES    OR   STIMULANTS. 

Ai.t  the  org-anic  manures,  when  burned,  leave  ashes  composed  of 
earthy  and  saline  substances.  The  action  of  these  substances  upon 
vegetation  is  quite  unquestionable,  and  it  is  certain  that  an  organic 
manure,  were  it  ever  so  rich  in  azotized  principles,  and  ever  so  as- 
similable, would  still  be  imperfect  did  it  not  further  contain  the  truly- 
mineral  matters  which  plants  require  to  meet  with  in  the  soil,  in 
order  to  complete  their  growth  and  bring  their  seeds  to  maturity. 
The  most  active  organic  manures  are  always  abundantly  provided 
with  inorganic  principles.  Farm  dung  (dry)  contains  about  one- 
fourth  of  its  weight  of  such  substances,  and  the  water  which  is  used 
for  irrigation  invariably  holds  saline  matter  in  solution. 

Nevertheless,  repeated  cropping  will  often  end  by  depriving  the 
soil  of  the  mineral  substances  which  plants  require  ;  the  salts  con- 
tained in  the  manure  supplied  are  sometimes  inadequate  to  meet 
the  demands  of  successive  crops,  and  then  the  return  falls  off.  It 
is  consequently  necessary  in  certain  cases  to  furnish  the  soil  anew 
with  saline  matters,  in  order  to  supply  the  continued  drain  that  is 
made  upon  it,  or  to  meet  the  exigencies  of  particular  crops  which 
are  known  to  require  an  unusually  large  quantity  of  salts  for  their 
successful  cultivation.  It  is  in  this  way  that  clover,  lucern,  and 
sainfoin  require  plaster,  (gypsum  ;)  the  cereals,  silica,  and  certain 
calcareous  salts  ;  the  vine,  potash,  &c. 

Practice  got  the  start  of  science  in  the  application  of  mineral  ma- 
nures or  stimulants.  If  their  useful  influence  cannot  be  denied,  as 
it  cannot,  if  the  circumstances  in  which  it  is  advantageous  to  admin- 
ister them,  if  the  conditions  and  the  doses  in  which  they  ought  to  be 
given  to  the  ground  have  been  the  subject  of  long  and  careful  obser- 
vation with  farmers,  it  must  still  be  admitted  that  we  are  far  from 
understanding  exactly  in  what  way  they  act ;  this  is  another  motive 
for  continuing  to  study  them  with  perseverance. 

CALCAREOUS    MANURES. 

In  certain  soils  we  have  said  that  the  calcareous  element  is  either 
wanting,  or  present  in  very  small  and  inadequate  quantity  ;  other 
soils,  again,  abound  in  calcareous  matter,  and  observation  appears  to 
prove  that  the  presence  of  carbonate  of  lime  in  a  soil  adds  unequivo- 
cally to  its  fertility.  The  majority  of  the 'good  wheat  lands  hitherto 
examined  have  been  found  to  contain  a  notable  quantity  of  this  earth 
or  earthy  salt. 

It  is  usual  to  put  lime  into  the  ground  in  the  state  of  caustic  or 
quick-lime  ;  this  is  liming^  properly  so  called.  But  it  is  also  ap- 
plied in  the  state  of  carbonate,  as  when  we  make  use  of  chalk  or 
marl,  or  shell-sand  from  the  sea-shore. 


304  LIMING. 

The  limestone  that  is  used  for  burning  is  seldom  pure;  it  fre- 
quently contains  clay,  quartzy  sand,  metallic  oxides,  and  occasionally 
carbonaceous  matter  ;  frequently  too  it  is  so  largely  mixed  with 
magnesia  that  it  acquires  peculiar  characters  ;  this  is  the  magnesian 
limestone  or  dolomite.  The  purest  carbonate  of  lime,  by  exposure 
for  some  time  to  a  white  heat,  loses  43.7  of  carbonic  acid,  and  con- 
sequently contains  56.3  of  caustic  lime.  Limestone  is  one  of  the 
most  common  of  rocks  ;  in  the  crystalline  and  saccharoid  state,  or 
of  closer  and  finer  grain,  it  often  constitutes  mountain  masses,  and 
is  met  with  in  every  part  of  the  geological  series ;  it  meet««  us  as 
chalk  in  beds  of  enormous  thickness,  filling  up  extensive  basins  in 
the  tertiary  series  ;  such  are  the  chalk  beds  of  the  south  and  west 
coasts  of  England,  extending  through  the  counties  of  Kent  and 
Sussex,  &c. 

The  only  mineral  substance  with  which  chalk,  limestone,  or  car- 
bonate of  lime  is  likely  to  be  confounded,  is  gypsum  or  sulphate  of 
lime.  But  it  is  easy  to  distinguish  either  of  these  salts  from  the 
other :  carbonate  of  lime  dissolves  with  eflfervescence  in  dilute 
hydrochloric  acid  ;  sulphate  of  lime  is  insoluble  in  this  liquid. 
Carbonate  of  lime  is  quite  insoluble  in  water ;  sulphate  of  lime  is 
very  sensibly  soluble,  and  a  copious  precipitate  falls  on  the  addition 
of  a  solution  of  oxalic  acid  or  of  oxalate  of  ammonia.  Gypsum  is 
always  so  soft  that  it  can  be  scratched  with  the  nail ;  limestone, 
save  in  the  state  of  chalk,  is  generally  so  hard  that  it  resists  the 
nail. 

The  i)urning  of  lime  for  agricultural  uses  is  carried  on  in  the  same 
way  as  for  building  and  other  economical  purposes.  Burnt  or  quick- 
lime is  a  very  different  article  from  chalk  or  limestone  ;  it  is  power- 
fully caustic  or  destructive  of  the  organic  tissue,  and  instead  of 
being  altogether  insoluble,  it  is  now  soluble  in  about  630  parts  of 
cold  water.  All  the  world  knows  how  lime  from  the  kiln,  when 
watered,  rises  in  temperature,  breaks  first  into  larger  and  then  into 
smaller  pieces,  and  finally  falls  down  into  fine  powder  ;  but  every 
one  is  not  aware  that  there  is  a  true  chemical  union  of  water  with 
the  earth,  and  that  the  resulting  powder  is  in  chemical  language  a 
hydrate  of  lime,  a  substance  which  is  much  less  caustic  than  pure 
lime,  but  s^till  distinctly  alkaline  in  its  reaction. 

It  is  generally  admitted  that  the  soil  which  is  without  a  certain, 
and  that  a  considerable  proportion  of  the  calcareous  element,  never 
possesses  a  high  degree  of  fertility.  This  in  particular  is  the  opin- 
ion of  English  agriculturists,  who  apply  lime  with  a  kind  of  profu- 
sion ;  and  the  great  improvement  it  frequently  produces  on  the  crops 
of  grain,  leaves  no  doubt  as  to  the  advantages  of  the  procedure. 
Still  it  is  now  generally  recognized  that  liming  ceases  to  be  useful 
upon  lands  that  are  already  sufliciently  calcareous,  or  that  rest  on  a 
sub-soil  of  chalk.  It  is,  therefore,  by  supplying  the  calcareous  ele- 
ment which  land  requires  to  constitute  it  a  soil  adapted  to  the  growth 
of  corn,  that  the  application  of  line  becomes  useful ;  liming,  in 
fa«t,  enables  us  to  make  this  neces&iry  addition  at  least  cost.  Like 
other  mineral  manures,  lime  of  itself  produces  little  or  no  eflfect; 


LIMING.  305 

it  is  in  concurrence  with  organic  manures  that  it  becomes  truly  use- 
ful ;  it  is  nowise,  and  never  can  become,  a  substitute  for  these. 

The  geological  constitution  of  a  country  is  perhaps  the  best  guide 
10  the  necessity  or  advantages  of  liming.  Soils  that  are  derived 
from  plutonic  or  igneous  rocks,  in  which  felspar,  mica,  or  quartz 
predominate,  are  on  the  face  of  things  likely  to  be  improved  by  the 
introduction  of  lime.  Direct  analysis  would  of  course  give  more 
decisive  information  on  the  fact.  In  any  case,  the  measure  recom- 
mended by  prudence  is  to  make  a  few  preliminary  trials  upon  the 
small  scale  ;  the  experimental  method  is  the  only  safe  one  in  agri- 
culture, when  the  question  is  in  regard  to  the  adoption  of  new  plans. 
In  England  it  is  customary  in  liming  clayey  lands  to  allow  from 
230  to  300  or  310  bushels  of  stimulant  per  acre  ;  on  lighter  soils 
the  dose  may  vary  from  about  150  to  200  bushels,  according  to  their 
character.  In  France  the  quantity  usually  employed  is  greatly  less, 
from  about  60  to  70  bushels  being  all  that  is  generally  thought  ad- 
visable, and  this  at  intervals  of  seven  or  eight  years-.  In  the  neigh- 
borhood of  Lisle  little  use  is  made  of  lime,  although  there  the  land 
is  generally  any  thing  but  calcareous ;  perhaps  the  want  of  lime  is 
not  felt  in  consequence  of  the  universal  practice  of  employing  the 
Flemish  manure,  which,  as  we  have  seen,  contains  ammoniacal 
salts,  (and  both  human  urine  and  excrement  contain  a  large  quantity 
of  phosphate  of  lime  and  phosphate  of  magnesia  in  addition,  the 
very  salts  that  the  generality  of  vegetables  crave.)  In  the  vicinity 
of  Dunkirk,  however,  lime  is  frequently  applied  in  the  dose  of  be- 
tween 40  and  50  bushels  per  acre,  and  with  eflfects  that  are  said  to 
continue  for  ten  or  twelve  years. 

The  dose  of  lime  introduced  into  the  soil  in  different  countries,  is 
moreover  in  a  certain  relation  with  the  time  during  which  the  action 
of  the  earth  is  believed  to  continue ;  as  the  quantity  administered  at 
once  is  small,  the  dose  must  be  repeated  more  frequently.  Near 
Dunkirk  they  use  from  40  to  50  bushels  per  acre  every  10  or  12 
years  ;  in  the  department  of  La  Sarthe,  according  to  M.  Puvis,  they 
scatter  on  some  9  or  10  bushels  only  ;  but  they  do  so  every  three 
years.  This  would  lead  us  to  conclude  that  soils  which  really 
wanted  lime  should  receive  a  dose  in  the  proportion  of  about  3^ 
bushels  per  acre  annually.  But  the  crops  gathered  from  the  ground 
every  year,  certainly  do  not  abstract  any  thing  like  this  quantity  of 
calcareous  matter ;  which  would  induce  us  to  infer,  that  after  a  cer 
tain  time  the  land  will  contain  such  a  quantity  of  lime  as  to  make 
any  further  addition  of  it  unnecessary,  or  at  all  events,  unnecessary 
save  at  rare  and  distant  intervals. 

One  of  the  great  advantages  which  lime  has  over  all  the  other 
forms  or  kinds  of  calcareous  stimulants  employed,  is  unquestionably 
the  state  of  extreme  subdivision  which  it  acquires  in  the  quenching. 
In  the  course  of  falling  down  into  this  extremely  fine  powder,  lime, 
as  has  been  said,  combines  with  a  large  quantity  of  water.  But  the 
change  experienced  does  not  stop  short  here  ;  the  air  always  contains 
some  lOjOOOths  of  carbonic  acid  gas,  for  which  the  hydrate  of  lime 
has  a  powerful  ailinity,  so  that  it  absorbs  this  gas  greedily,  aban- 

26* 


806  LIMING. 

doninff,  at  the  same  time,  its  constitutional  water,  by  which,  in  due 
season,  the  hydrate  of  lime  becomes  changed  into  the  anhydrous 
carbonate  of  lime.  This  process  is  always  slow ;  more  rapid  at 
first,  when  the  interchange  between  the  carbonic  acid  and  watei 
takes  place  freely  ;  it  becomes  gradually  slower  and  slower  as  there 
is  less  and  less  water  left  in  the  particles :  the  affinity  of  the  lime 
for  the  water  seems  to  increase  continually  in  the  ratio  of  the  small- 
ness  of  the  quantity  which  it  still  contains.  It  must,  therefore,  con 
stantly  happen  that  in  incorporating  lime,  in  powder  and  partially 
carbonated  with  the  soil,  we  also  introduce  lime  that  has  preserved 
its  causticity  in  some  measure  ;  it  must  be  observed,  however,  that, 
once  intimately  mixed  with  the  soil,  this  lime  must  speedily  pass 
into  the  state  of  carbonate,  because  the  soil  and  the  water  with  which 
it  is  moistened  always  contain  a  considerable  quantity  of  carbonic 
acid.  Though  we  commence  operations  with  quick-lime,  conse- 
quently, it  is  carbonate  of  lime  that  is  definitively  introduced  into  the 
ground.  1  have  thought  this  a  point  of  sufficient  importance  to  en- 
gage our  attention  for  a  short  time,  inasmuch  as  it  simplifies  the 
view  of  the  end  that  is  to  be  sought  in  applying  lime;  this,  as  M. 
Puvis  has  most  satisfactorily  established,  is  neither  more  nor  less 
than  the  introduction  into  the  ground  of  that  proportion  of  the  calca- 
reous element  which  it  either  wanted  originally,  or  which  it  has  lost 
in  the  course  of  repeated  cropping,  in  order  to  enable  it  to  produce 
abundantly.  Quick-lime  incorporated  with  the  soil  must  pass,  as  I 
have  shown,  very  rapidly  into  the  state  of  carbonate ;  but,  before 
attaining  to  this  state,  it  may,  unquestionably,  react  upon  the  organic 
substances  it  encounters,  disorganize  them,  favor  their  decomposi- 
tion, in  a  word,  behave  as  it  does  when  used  in  composts.  On  the 
other  hand,  in  causing  the  destruction  of  organic  particles  already 
in  a  state  of  decomposition,  it  must  produce  an  unfavorable  influ- 
ence. 

Lime,  previously  quenched  and  cold,  is  generally  spread  by  being 
raked  out  from  the  cart  upon  the  field,  in  little  heaps,  from  five  to  six 
or  seven  yards  apart,  each  containing  from  half  to  two-thirds  of  a 
bushel.  It  is  or  ought  then  to  be  spread  immediately  as  evenly  as 
possible  over  the  surface.  There  is  only  the  disadvantage  attending 
this  mode  of  proceeding,  that  slaked  lime  is  twice  the  bulk  of  lime 
in  the  shell  or  lump,  and  that,  by  slaking,  it  takes  up  at  least  one- 
fifth  of  its  original  weight  of  water.  There  is  saving  of  labor, 
therefore,  in  distributing  the  lime  unslaked,  in  heaps,  and  waiting  the 
slow  process  of  extinction  and  pulverization  by  the  moisture  of  the 
atmosphere.  The  lime  is  often  laid  in  a  corner  of  the  field,  and 
covered  lightly  over  with  vegetable  earth  to  undergo  pulverization, 
and  this  plan  answers  very  well.  Sometimes  the  lime,  before  being 
laid  on,  is  worked  up  into  a  kind  of  compost  with  vegetable  mould 
and  other  matters ;  this  is  all  matter  of  calculation  as  to  cost.  If 
our  object  be  to  supply  the  soil  with  the  calcareous  elements  it  wants, 
the  proper  procedure  is  quite  obvious. 

The  mode  of  using  lime  with  reference  to  other  improvers  of  the 
•oil  vaiies  in  different  places.     In  one  place  it  is  usual  to  lime  and 


MARL.  30t 

to  dung  alternately  ;  in  others,  the  two  operations  are  done  together, 
or  very  close  upon  one  another.  There  are  some  lands  so  fertile, 
that  they  produce  abundantly  under  the  influence  of  lime  alone.  In 
laying  on  lime,  one  general  rule  is,  that  the  weather  should  be  dry, 
and  the  ground  well  drained ;  the  end  of  summer  is  probably  the 
most  favorable  season.  To  say  nothing  of  the  difficulty  of  spreading 
the  lime  in  wet  weather,  if  it  is  at  all  fresh,  its  caustic  qualities  are 
brought  into  immediate  play  by  the  moisture,  and  it  destroys  the 
roots  of  living  vegetables,  and  the  organic  elements  of  the  soil ;  and, 
again,  it  is  quite  certain  that  lime  produces  very  little  effect  upon 
undrained  and  wet  lands.  In  England,  lime  is  very  commonly  used 
upon  fallows,  in  the  course  of  the  summer,  and  before  sowing  the 
wheat  for  which  fallowing  is  always  a  preparation.  When  it  is  given 
to  land  destined  for  beet  or  potatoes,  it  is  led  out  in  the  spring,  and 
spread  before  the  young  beet  is  transplanted,  in  the  one  case,  the 
seed-potatoes  deposited,  in  the  other. 

It  is  always  matter  of  great  moment  to  have  lime  spread  evenly  ; 
a  thorough  harrowing  and  a  double  superficial  ploughing  incorporate 
it  sufficiently.  According  to  M.  Puvis,  who  has  made  a  particular 
study  of  the  subject  of  liming,  as  practised  in  the  department  of  the 
Ain,  a  quantity  of  lime,  amounting  to  8,250  bushels,  spread  upon 
seventy-seven  acres  of  land,  in  the  course  of  nine  years,  produced 
so  decided  an  improvement  that  the  returns  from  winter-grain  crops 
became  the  double  of  what  they  had  been  before. 

Marl.  Marl,  in  a  general  way,  may  be  regarded  as  a  mixture  of 
carbonate  of  lime  and  clay  in  very  variable  proportions.  Occasional- 
ly the  clay^is  replaced  by  sand  ;  whence  the  titles,  sandy  marl,  argil- 
laceous marl.  The  article,  in  short,  contains  from  15  to  as  many  as 
90  per  cent,  of  carbonate  of  lime.  It  presents  numerous  shades  of 
color.  Geologically  speaking,  it  is  usually  met  with  in  fresh-water 
formations  of  the  latest  date — the  upper  strata  of  the  Jura  limestone 
are  frequently  covered  with  deposites  of  argillaceous  marls,  and  we 
see  its  formation  going  on  at  the  bottoms  of  lakes  and  ponds,  at  the 
present  day. 

The  distinguishing  property  of  a  calcareous  marl,  whatever  ad- 
mixture of  other  matters  it  contains,  is  that  of  crumbling  to  pieces 
under  exposure  to  atmospherical  influences.  Every  limestone  rock 
that  has  this  property  may  be  considered  and  employed  as  a  marl. 
The  grand  purpose  of  putting  marl  upon  land  is  to  supply  it  with  the 
calcareous  element  it  wants.  To  marl  land,  is  therefore  tantamount 
to  liming  it :  the  effect  is  the  same.  The  value  of  the  article  is, 
indeed,  so  well  known,  that  considerable  expense  is  constantly  in- 
curred to  get  at  the  beds  of  it  that  form  strata  in  the  crust  of  tae 
earth,  or  that  lie  at  the  bottoms  of  lakes.  It  appears  to  have  been 
employed  from  the  remotest  antiquity. 

The  reason  why  marl  and  marly  limestones  fall  so  completely 
into  powder,  is  obvious.  If  the  mass,  when  wet,  form  a  pasty  mass- 
it  shrinks  as  it  dries,  and  cracks  in  all  directions  ;  if  more  consistent, 
it  is  still  always  porous,  and  having  imbibed  a  large  quantity  of  rain 
in  the  autumn,  this  congeals  during  the  frosts  of  t.he  succeeding  win- 


308  MARL. 

ter,  and  the  ice,  expanding  with  almost  irresistible  force,  separates 
the  particles,  which  cohere,  indeed,  so  long  as  the  frost  continues, 
but  fall  away  from  one  another  on  the  first  thaw,  by  which  the  solid 
rock  of  the  autumn  and  winter  becomes  a  heap  of  dust  in  the  spring. 
In  the  same  way,  we  see  chalk,  exposed  to  the  wet  and  the  frost, 
fall  down  to  powder,  and,  in  virtue  of  this  property,  and  its  constitu- 
tion as  carbonate  of  lime,  employed  with  perfect  success  in  lieu  of 
lime  and  marl.  Wherever  there  is  a  bed  of  chalk  at  hand,  it  is  need- 
less to  go  further  in  search  of  marl  and  quick-lime,  in  so  far  at  least 
as  the  calcareous  principle  is  concerned. 

Argillaceous  marl  and  sandy  marl  must,  of  course,  act  in  two 
different  ways  upon  the  soil :  in  virtue  of  the  calcareous  element  in 
either  case,  and  in  virtue  of  the  argillaceous  principle  in  the  one, 
of  the  sandy  principle  in  the  other  ;  and  the  kind  of  soil  for  which 
they  are  severally  adapted  can  be  conceived  beforehand.  To  a  stiff, 
clayey  soil,  we  would  naturally  add  the  sandy  marl;  to  a  light  sandy 
soil  we  would  supply  the  argillaceous  product,  and  thus  effect  im- 
provement by  a  kind  of  double  tide.  It  is  therefore  very  important  to 
distinguish  between  these  two  effects  produced  by  marl — one  me- 
chanical, connected  with  the  presence  of  clay  or  sand  ;  the  other 
chemical,  and  depending  on  the  presence  of  carbonate  of  lime.  It  is 
to  these  two  effects,  separately  and  combined,  that  all  the  influence 
of  marl  is  usually  ascribed  by  practical  agriculturists.  From  certain 
inquiries  common  to  M.  Payen  and  me,  however,  it  appears  that 
marl  must  act  in  yet  another  way  ;  our  analyses  show  that  it  always 
contains  a  certain  though  variable  proportion  of  azotized  matter. 
And  there  is  nothing  extraordinary  in  the  discovery  of  this  fact ;  it 
is  no  more  than  might  have  been  anticipated  from  the  ge(^ogical  cir- 
cumstances attending  its  production.  Marls  are,  as  has  been  said, 
always  connected  with  the  most  recent  formations  of  the  tertiary 
series  ;  they  are  constantly  accompanied  by  remains,  which  attest 
the  presence  of  organic  beings,  and  frequently  they  consist  of  little 
else  than  shells,  and  the  disintegrated  dwellings  and  bodies  of  mo- 
luscas,  and  madrepores,  and  corallines,  and  other  inferior  forms  of 
things  that  once  had  life.  It  is  by  no  means  astonishing,  therefore, 
that  deposites  which  have  had  such  an  original  should  still  contain 
evidences  of  the  presence  of  the  softer  and  more  decompoundable,  as 
well  as  of  the  harder  and  more  rebellious  constituents  of  the  beings 
to  whose  existence  they  are  due.  One  sample  of  marl  which  we 
analyzed,  gave  0.002  of  azote  ;  another,  from  the  Lower  Rhine, 
gave  rather  more  than  0.001  of  the  same  element.  It  were,  there- 
fore, very  proper,  in  analyzing  marls,  chalks,  &c.,  to  have  an  eye  tc 
their  organic  or  azotic,  as  well  as  to  their  mineral  constituents  ;  there 
can  be  very  little  question  of  the  azotized  elements  being  at  the  bot 
torn  of  the  really  wonderful  fertilizing  influences  of  the  marls  of 
certain  districts. 

Marl  ought,  like  lime,  to  be  spread  very  evenly  over  the  land  ;  i 
is  generally  laid  on  in  the  same  way  as  lime — in  little  heaps  at  re 
gular  distances,  and  then  scattered  abroad.  It  appears  to  be  a  verj 
general  opinion  that  it  is  not  advisable  to  cover  it  immediately,  or  verj 


309 

shortly  after  it  is  dug  from  the  bed  that  supplies  it ;  the  practice 
where  its  employment  is  most  general,  and  probably  best  understood, 
is  to  let  it  lie  exposed  through  the  summer  or  winter,  or  even  the 
whole  year  before  laying  it  on  the  land.  It  is  also  held  not  to  be 
proper  to  cover  it  in  marl  deeply.  Marl  is  advantageously  laid  out 
in  heaps  upon  stubbles  in  the  autumn ;  and  in  the  early  spring  when 
it  has  been  pulverized  by  the  frost,  it  is  spread  with  the  shovel. 
When  it  is  to  be  used  with  winter  wheat  or  rye,  it  is  laid  on  in  the 
summer,  and  spread  at  the  time  of  ploughing ;  the  latter  plan  of 
proceeding,  however,  as  Schwertz  observes,  can  only  be  followed 
with  marl  that  pulverizes  readily.  In  England  it  is  also  laid  down 
as  a  kind  of  principle  that  marl  ought  to  be  exposed  for  as  long  a 
time  as  possible  to  the  influences  of  the  atmosphere ;  that  it  ought 
to  have  a  summer's  heat  and  a  winter's  cold  before  it  is  applied. 
And  that,  in  fact,  which  is  at  all  consistent,  and  has  not  been  expos- 
ed to  the  frost,  scarcely  pulverizes  sufficiently  to  be  readily  miscible 
with  the  soil  even  under  the  influence  of  repeated  ploughings  ;  more- 
over, it  produces  very  little  obvious  ejSfect  upon  the  crop  with  which 
it  is  first  used.  After  spreading,  a  rough  harrow  is  passed  over  the 
surface  of  the  ground,  which  is  then  ploughed  superficially  two  or 
three  times,  the  harrow  being  again  had  recourse  to  repeatedly  to 
break  lumps,  and  so  bring  out  the  effect  of  the  marl. 

The  quantity  of  marl  that  may  be  advantageously  given  varies 
according  to  the  circumstances  of  the  district.  Marl,  it  may  fairly 
be  said,  is  frequently  abused.  In  an  excellent  paper  on  the  subject, 
M.  Puvis  lays  it  down  as  a  principle  that  the  first  element  in  the 
calculation  of  the  proper  dose  of  marl,  is  the  quantity  of  calcareous 
matter  that  is  wanting  in  the  soil.  He  says  that  every  soil  which 
contains  Q^iore  than  9  or  10  per  cent,  of  carbonate  of  lime  can  dis- 
pense with  marl  ;  and  that  soils  in  which  the  lime  falls  short  of  this 
quantity,  may  advantageously  receive  a  dose  or  successive  doses  of 
the  substance  that  will  bring  them  up  to  the  point.  The  proper 
dose,  consequently,  depends  first  on  the  proportion  of  carbonate  of 
lime  contained  in  the  soil,  and  then  on  that  which  the  marl  itself 
includes. 

Considered  from  the  rational  point  of  view  which  M.  Puvis  has 
taken,  marling  is  no  longer  an  arbitrary  process,  but  one  that  may 
be  conducted  on  determinate  principles.  The  extravagant  quanti- 
ties that  are  often  laid  on  without  other  assignable  reason  than  blind 
custom,  are  shown  to  be,  if  not  injurious,  yet  useless  :  the  quantity 
of  marl  to  be  incorporated  is  determined  by  the  quality  of  the  sub- 
stance which  is  at  our  disposal,  and  by  the  depth  of  the  layer  of 
vegetable  ea~th  taken  in  connection  with  its  chemical  constitution. 
To  facilitate  the  calculation  of  the  proper  dose,  M.  Puvis  has  drawn 
up  a  table,  which,  as  it  may  be  found  useful  in  practice,  I  append. 
It  shows  at  a  glance  the  quantity  of  marl  in  cubic  feet  that  ought  to 
be  put  upon  an  acre  of  ground,  the  depth  of  the  arable  soil  being 
considered  in  connection  with  the  composition  of  the  marl  at  com-> 
laand :— 


SIO 


MARL. 


Table  of  the  Number  of  Cubic  Feet  of  Marl  applicable  upon  an 

When  100 

Acre  of  Land  ploughed  to  the  depth  of: 

parts  of  marl 

contain  of 

carbonate  of 

lime. 

inches. 

inches. 

Sr^TT 

6fV 

7tV 

8A 

inches. 

inches. 

inches. 

inches. 

333 

444 

554 

666 

776 

888 

10 

1661 

222 

277 

333 

388 

444 

20 

111" 

146 

184^0 

222 

258^ 

296 

30 

83-iV 

HI 

138fV 

166fV 

194 

222 

40 

-66fV 

88tV 

llOrV 

133^V 

155rV 

177y3^- 

50 

55r\ 

74 

^'^^ 

111 

129y2^ 

148 

60 

47A 

63A 

79A 

95^ 

iioA 

126A 

70 

41t^ 

55  fV 

69t^ 

83f^ 

97 

111 

80 

37 

49t^o 

6li 

74 

86t^ 

98T'ff 

90 

33^ 

44A 

55>o 

66A 

77^ 

88A 

100 

M.  Puvis  does  not  by  any  means  give  the  doses  in  this  table  as 
those  that  should  be  invariably  employed  ;  the  table  is  one  of  aver- 
ages, deduced  from  practical  results,  and  tested  by  experience  as 
most  truly  useful.  But  special  cases  may  occur  that  would  make 
departure  from  these  conclusions  not  only  advisable,  but  advantage- 
ous.* 

The  use  of  marl  produces  an  unquestionable  effect  on  the  pro- 
ductive properties  of  the  soil.  According  to  M.  Puvis,  the  applica- 
tion of  the  proper  dose  of  a  sandy  marl,  containing  from  30  to  60  per 
cent,  of  carbonate  of  lime,  doubled  the  produce  of  a  piece  of  parched 
land  in  the  department  of  the  Isere.  Before  the  application  of  the 
marl  nothing  but  dwarfish  crops  of  rye  were  gathered,  yielding  at 
most  three  for  one  of  the  seed ;  at  present,  eight  for  one  of  seed, 
and  that  wheat,  are  obtained ;  and  the  good  effects  are  found  to 
continue  for  ten  and  even  twelve  years. 

The  action  of  marl  is  not  unlimited  any  more  than  that  of  lime, 
as  the  last  sentence  will  give  the  reader  reason  to  conclude.  With 
every  harvest,  a  certain  proportion  of  it  is  carried  off,  and  the  land 
is  finally  left  with  an  inadequate  quantity  of  the  calcareous  element, 
which  then  requires  to  be  restored.  The  nature  of  the  crop,  how- 
ever, has  the  most  marked  influence  on  the  quantity  of  lime  that  is 
taken  up  and  carried  away  from  the  soil  ;  allowing  the  broadest 
margin,  and  judging  from  the  composition  of  the  ashes  of  the  plants 
that  form  the  subjects  of  our  ordinary  crops,  we  can  see  that  the 
quantity  of  3|  bushels  of  marl  of  the  usual  composition  per  acre, 
which  is  assumed  as  the  average  quantity  to  be  laid  on,  is  vastly 
more  than  can  be  absolutely  necessary. 

Wood  ashes  contribute  to  improve  the  soil.  They  contain,  besides 
fiilica,  both  phosphate  and  carbonate  of  lime  and  alkaline  sulphates, 
phosphates,  and  carbonates.     In  a  general  way,  every  thing  derived 

♦  Puvis  in  Annals  of  French  AgricuUuro,  vol.  xxviii.  p.  328,  2d  series. 


PEAT   ASHES.  311 

fraia  plants  that  have  lived  must  be  useful  to  plants  that  are  about 
to  live,  or  that  are  actually  living.  Although  the  utility  of  wood 
ashes,  then,  is  generally  admitted,  the  numerous  purposes  to  which 
they  are  applied  in  the  arts,  and  their  high  price,  which  is  the  con- 
sequence of  this,  enable  the  husbandman  to  employ  them  but  rarely 
on  his  land  ;  they  are  almost  always  lixiviated  in  order  to  procure 
the  carbonate  of  potash  they  contain.  In  countries  which  are  thick- 
ly wooded,  indeed,  the  trees  are  actually  cut  down  and  burned  for 
the  sake  of  their  ashes,  just  as  oxen  are  run  down  and  slaughtered 
in  the  vast  plains  of  South  America  for  the  sake  of  their  hides. 

The  good  effect  of  wood  a"shes  upon  vegetation  is  known  to  com- 
munities the  least  advanced  in  civilization.  The  Indians  of  South 
America  burn  the  stems  and  leaves  of  the  maize  in  order  to  improve 
the  soil.  The  same  practice  occurs  among  the  natives  of  Africa  : 
on  the  banks  of  the  river  Zaire,  according  to  Tuckey,  the  ground  is 
prepared  by  having  little  piles  of  dried  herbs  placed  on  it,  to  which 
fire  is  set ;  and  upon  the  spots  where  the  ashes  are  collected,  they 
sow  peas  and  Indian  corn  ;  these  ashes  are  in  fact  the  only  manure 
that  is  employed.  In  England,  wood  ashes  are  esteemed  as  parti- 
cularly useful  upon  gravelly  soils  ;  about  40  bushels  per  acre  are 
applied  in  the  spring,  where  the  article  can  be  obtained. 

The  lye-ashes  from  the  soap-boiler  contain  a  small  quantity  of 
soluble  saline  matter  which  has  escaped  the  lixiviation,  mixed  with 
a  large  proportion  of  lime,  partly  in  the  state  of  carbonate,  the  lime 
having  been  added  to  bring  the  carbonate  of  potash  employed  in  the 
manufacture  of  soap  into  the  caustic  state.  This  ash  or  refuse  is 
much  sought  after,  and  is  administered  in  quantities  that  vary  from 
45  to  70  bushels  per  acre,  a  dose  in  which  its  action  is  felt  for  ten 
years  or  more.  In  wooded  districts,  where  there  is  a  good  deal  of 
potash  prepared,  ash  of  this  kind  is  obtained  in  large  quantity  ;  it  is 
there  employed  alternately  with  organic  manures.  Ashes  are  ap- 
plied in  th«  same  way  as  lime,  with  this  difference,  that  it  is  held 
better  not  to  plough  them  in  until  they  have  received  a  little  rain. 
There  tre  places  where  the  ashes  that  remain  in  the  lixiviating  tub 
are  threwn  on  in  the  dose  of  170  bushels  per  acre. 

Turf  or  peat  ashes.  Peat  is  the  result  of  a  peculiar  spontaneous 
change  that  takes  place  in  vegetables.  It  is  produced  in  bogs  or 
swamps,  and  in  connection  with  stagnant  waters  ;  turfy  deposites  are 
also  encountered  on  the  banks  of  rivers,  in  valleys,  at  the  bottoms 
of  former  lakes,  and  at  the  mouths  of  rivers.  Peat  is  met  with 
from  the  level  of  the  sea  to  the  elevated  platforms  of  the  Vosges 
and  x\lps  ;  it  lies  in  horizontal  beds,  frequently  divided  by  strata  of 
gravel,  sand,  or  clay.  It  is  always  a  product  of  comparatively  re- 
cent formation,  a  fact  which  is  attested  by  the  thin  layers  of  vege- 
table soil  that  lie  over  it  in  many  places,  and  the  animal  remains 
and  products  of  human  industry  that  are  frequently  encountered 
in  it. 

The  state  of  decomposition  of  the  vegetables  that  form  turf  or 
peat  is  seldom  so  far  advanced  as  to  make  the  remains  of  the  plants 
which  compose  it  doubtful.     It  is  of  different  kinds  :  hard  or  woody, 


S13  P£AT  ASHES. 

*nd  sof>  o»  hffbajeois  peat.  Some  of  it  is  extremrly  compact. 
Mack,  and  like  vegetable  mould  in  appearance;  generally  speaking 
it  is  light,  spongy,  ind  of  a  lighter  or  deeper  shade  of  brown. 
When  quite  dry,  it  is  often  extremely  light ;  a  fiub  c  metre,  which 
is  about  one-eleventh  more  1  han  a  c»ibic  yard,  wil «  weigh  from  5  to  6 
cwt. 

The  circumstances  in  which  turf  has  been  found  lead  us  to  infer 
that  it  must  contain  the  elementary  insoluble  elements  of  the  plants 
that  produced  it.  It  appears,  however,  to  contain  a  somewhat  lar- 
ger proportion  of  azote  than  the  average  quantity  met  with  in  her- 
baceous vegetables,  supposed  dry ;  but  we  have  seen  that  in  the 
slow  alteration  of  lignine,  azote  becomes  concentrated,  as  it  were, 
in  the  residue ;  and  that,  in  fine,  mould  contains  a  larger  quantity  of 
azote  than  the  wood  from  which  it  proceeds.  It  appears  further 
from  some  experiments  very  lately  performed  by  Mr.  Hermann,  that 
during  the  putrefaction  of  the  woody  principle,  azote  is  actually  ta- 
ken from  the  air  to  concur  in  the  formation  of  certain  products  that 
are  perfectly  definite.  Mr.  Hermann  quotes  the  following  experi- 
ment : 

Twenty-eight  parts  of  wood  taken  from  a  log  already  attacked 
with  rot,  and  in  which,  indeed,  there  were  several  points  already 
decayed,  were  moistened  and  enclosed  in  a  jar  containing  atmo- 
spherical air  over  mercury.  The  bulk  of  the  atmosphere  contained 
in  the  bell-glass  was  262  volumes.  The  wood  was  kept  there  for 
ten  days  at  a  temperature  of  75.2°  Fahr.  The  apparent  volume  of 
the  air  continued  unaltered  to  the  end  of  the  experiment ;  but  a 
large  quantity  of  carbonic  acid  had  been  formed  : 

RESULTS  ON  THE   INCLUDED  AIR. 


The  air  cont^ned :  Azote. . . . 
Oxygen . 

Before. 
..207  vols. 

...   55 

Carbonic  acid... 

After. 
194  vols. 
...40    " 

28    " 

The  moist  wood  in  its  decomposition  during  ten  days  had  conse- 
quently caused  thirteen  volumes  of  azote  and  twenty-seven  volumes 
of  oxygen  to  disappear.  And  Mr.  Hermann  found  that  it  now  con- 
tained principles  analogous  to  those  of  humus,  one  of  which,  nitro- 
iin,  is  highly  azotized,  and  by  the  ulterior  action  of  air  and  moisture, 
gives  rise  to  ulraate  of  ammonia.  These  experiments  of  Mr.  Her- 
mann are  new,  and  the  conclusions  to  which  they  lead  are  both  inter- 
esting and  important.* 

Turf  or  peat  is  virtually  the  woody  principle  in  the  last  stage  of 
modification  by  atmospherical  influences  ;  but  it  appears  still  to  con- 
tain, although  modified,  the  usual  principles  which  enter  into  the 
constitution  of  herbaceous  vegetables  also,  M.  Payen  detected  a 
quantity  of  fatty  matter  in  it,  analogous  to  that  which  exists  in 
leaves,  and  M.  Reinsch  found  it  to  contain  tannin.     One  sample  of 

♦  Vide  hia  paper  in  Journ.  fiir  prakt.  Cliemie,  b.  xxUi.  s.  379. 


?EAT   ASHES.  31^ 

turf  (from  the  neighborhood  of  Moscow,  by  the  way)  examined  by 
Mr.  Hermann,  yielded  of  carbonaceous  matter,  nitrolin  and  vegeta- 
ble remains  77.5  ;  of  ulmic  acid  17.0 ;  extract  of  humus  4.0  ;  am- 
monia 0.25  ;  and  ash  1.25=100.0  The  elementary  composition  of 
these  varieties  of  turf,  analyzed  oy  M.  Regnault,  gave  from  57  to 
58  of  carbon  ;  5.1  to  5.6  hydrogen  ;  30.8  to  31.8  oxygen  and  azote  ; 
and  4.6  to  5.6  ashes. 

Turf  or  peat  has  consequently  a  certain  resemblance  to  mould  or 
.humus ;  it  differs,  hovvever,  in  the  absence  of  substances  soluble  in 
water ;  and  it  is  easy  to  imagine  that,  produced  as  it  is  in  connection 
with  water,  continually  soaked  in  moisture,  soluble  matters  ought 
«ot  to  be  expected  in  it  in  appreciable  quantity.  Peat  might,  in 
fact,  be  likened  to  the  insoluble  part  of  humus  left  after  lixiviation. 
A.nd  there  is  this  further  resemblance,  that  peat,  like  the  humus 
(vhich  has  been  thoroughly  lixiviated,  if  exposed  to  the  air,  by  and 
iy  acquires  a  quantity  of  soluble  material,  the  evolution  of  which  is 
also  hastened  by  the  contact  of  the  alkalies.  The  employment  of 
hirf  as  manure,  in  some  countries,  confirms  the  propriety  of  this 
mode  of  viewing  its  nature  and  constitution ;  and  then  it  is  well 
knowc  that  bogs  consisting  of  pure  turf,  when  drained  and  limed, 
become  tolerably  fertile  lands,  yielding  magnificent  crops  of  oats 
and  turnips  especially. 

The  ashes  of  turf  we  might  expect  to  contain  the  mineral  sub- 
stances usually  found  in  the  ashes  of  plants,  and  further  a  certain 
quantity  of  additional  earthy  matter.  But  this  is  not  the  case  :  sev- 
eral alkaline  salts,  indeed,  have  been  discovered  in  very  small  pro- 
portion ;  but  no  chemist,  to  my  knowledge,  has  ever  even  suspected 
the  presence  of  any  of  the  phosphates  ;  a  special  search  which  was 
made  for  them  in  my  laboratory  failed  to  discover  them.  This  is  a 
fact  which,  I  own,  amazed  me ;  some  coal  ash,  and  another  ash 
produced  from  lignite,  gave  a  result  equally  negative.  We  might 
imagine  the  disappearance  of  the  soluble  salts ;  but  how  the  earthy 
phosphates  should  disappear ;  how  the  ashes  of  coal  should  come 
to  be  without  a  trace  of  phosphoric  acid,  when  we  see  that  the  iron 
ore,  in  connection  with  the  coal  fields,  is  always  more  or  less  phos- 
phorigerous,*  is  surprising. 

Turf  or  peat  ashes  are  valuable  improvers  of  the  soil,  and  are  in 
Treat  request  among  intelligent  farmers.  Analysis,  in  fact,  indicates 
several  substances  in  their  composition  as  calculated  to  assist  vege- 
tation;  carbonate  of  lime,  in  a  state  of  extreme  subdivision  ;  occa- 
sionally sulphate  of  lime,  (gypsum ;)  calcined  clay,  whose  action 
upon  strong  and  retentive  lands  is  always  beneficial ;  silica  in  a  fa- 
vorable state  for  assimilation  ;  finally,  alkaline  salts,  chlorides,  sul- 
phates, carbonates,  and,  perhaps,  in  spite  of  the  negative  given  by 
chemical  analysis,  traces  of  the  phosphates. 

The  peat  of  the  bogs  of  Sceaux,  near  Chiteau-Landon,  leaves  19 
per  cent  of  ashes,  composed,  according  to  M.  Berthier,  of : — 

*  Our  author  might  have  added  the  fact,  that  the  common  bog  iron  ore  of  this  COUB 
try  is  a  phosphate  of  iron.— Eng.  Ed. 

27 


814  PEAT   ASHES. 

Caustic  and  carbonated  lime* • 83.C 

Clay 7JS 

Gelatinous  silica 13.0 

Alumina .t. 7.0 

Oxide  of  iron 9.0 

Car^..  late  of  potash 0.5 

100.0 

The  peat  of  Voiuomra,  dug  upon  the  frontiers  (.£  Bavaria  and 
Bohemia,  contains  the  remains  of  trees  ;  it  leaves  1.7  per  cent,  of 
ashes,  composed,  according  to  M.  Fikenscher,  of: 

Silica 36.5 

Alumina 17.3 

Oxide  of  iron 33.0 

Lime 2.0 

Magnesia  ••'. 3.5 

Sulphate  of  lime 4.5 

Chloride  of  calcium 0.5 

Carbonaceous  matter  not  incinerated —  2.7 

100.0 

The  brown  herbaceous  peat  of  the  neighborhood  of  Troyes,  leave* 
1 1  per  cent,  of  residue  ;  it  contains  : 

Carbonic  acid  and  sulphur 23.0 

Lime 23.0 

Magnesia 14.0 

Alumina  and  oxide  of  iron 14.0 

Clay  and  silica 26.0 

100.0 
The  peat  of  Vassy  is  compact,  and  of  a  brown  color;  it  is  mixed 
with  fragments  of  chalk.     On  incineration,  it  leaves  7.2  of  residue 
per  cent.,  containing : 

Clay 11.0 

Carbonate  of  lime 51.4 

Sulphateof  lime 26.0 

Oxide  of  iron 11.5 

100.0 

The  peat  of  Champ-du-Feu,  near  Framont,  (Vosges,)  leaves  3 
per  cent,  of  ashes,  which  consist  of: 

Silica 40.0 

Alumina  and  oxide  of  iron 30.0 

Lime 30.0 

100.0 

The  peat  of  the  environs  of  Haguenau  (Lower  Rhine)  produces 
12.5  per  cent,  of  ashes,  which,  according  to  the  analysis  made  in  my 
laboratory,  contain  : 

Silica  and  sand 65.5 

Alumina 16.2 

Lime 6.0 

Magnesia 0.6 

Oxideofiron 3.7 

Potash  and  soda "...  23 

Sulphuric  acid 5.4 

Chlorine 0.3 

10(.0 

Supposing  the  whole  of  the  sulphuric  acid  fciund  to  have  beeu  m 


COAL-ASHES.  315 

comoination  with  lime,  this  peat  could  only  ha^e  contained  4.1  per 
cent,  of  gypsum. 

These  analyses  will  show  that-the  composition  of  peat,  or  turf,  is 
very  various.  The  varying  and  dissimilar  effects  produced  by  turf- 
ishes,  may  probably  be  owing  to  this  variety  of  composition.  Turf- 
ashes,  in  a  general  way,  may  be  used  as  a  substitute  for  gypsum ; 
but  this  is  upon  the  presumption  that  they  contain  lime,  either  in  the 
state  of  carbonate  or  of  sulphate.  The  Vassy  turf-ashes,  for  ex- 
ample, may  be  employed  for  gypsing  meadows,  inasmuch  as  they 
contain  a  quarter  of  their  weight  of  sulphate  of  lime. 

The  ashes  from  pyritic  turf  ought  not  to  be  used  without  great 
circumspection ;  they  usually  contain  a  quantity  of  iron  pyrites 
which  has  not  been  destroyed  in  the  burning,  and  which,  exposed 
to  the  action  of  the  air,  gives  rise  to  the  formation  of  green  vitriol, 
or  sulphate  of  iron,  which  may  prove  prejudicial  to  vegetation. 
These  ashes  are  generally  of  a  red  color,  and  very  heavy,  in  con- 
sequence of  containing  a  quantity  of  the  oxide  of  iron.  Good  turf- 
ashes  ought  to  be  white  and  light ;  the  sack  ought  to  weigh  some- 
thing less  than  a  hundred-weight.  Schwertz  recommends  us  to  keep 
them  from  the  wet ;  but  at  Bechelbronn,  where  we  use  large  quanti- 
ties of  peat-ashes,  we  find  no  ill  effects  from  leaving  them  exposed 
to  the  rain ;  frequently,  indeed,  we  moisten  them  with  water  from  the 
dunghill,  in  order  to  add  to  their  properties  as  a  mineral  manure,  those 
that  belong  to  organic  manures.  On  the  whole,  however,  it  is  cer- 
tainly better,  for  many  reasons,  to  keep  them  dry  ;  they  are  more 
easily  carried,  and  they  are  more  easily  spread. 

Turf-ashes  of  a  good  quality,  that  is  to  say,  which  include  in  theii 
composition  a  large  proportion  of  calcareous  and  alkaline  salts,  are 
adapted  to  crops  of  every  description ;  but  it  is  upon  clover  especially 
that  their  influence  is  truly  surprising.  This  fact  is  well  established 
in  Flanders ;  but  one  must  have  employed  them  one's  self  to  have  any 
adequate  idea  of  the  improvement  they  produce.  There  is  no  risk 
of  giving  too  large  a  quantity.  In  winter,  when  we  have  peat-ashes 
at  our  disposal,  we  give  as  many  as  60  bushels  per  acre  to  our  clo- 
vers ;  we  scatter  them  even  upon  the  surface  of  the  snow,  and  dis- 
tribute them  by  means  of  the  rake  in  the  spring.  The  Dutch  use 
these  ashes  in  still  larger  quantity,  applying,  at  two  different  times, 
from  100  to  160  bushels  per  acre  to  their  clover  fields.  Accord- 
ing to  Sinclair,  the  Dutch  also  make  use  of  an  ash  procured  from 
a  turf  which  during  winter  is  in  contact  with  brackish  water,  a  cir- 
cumstance which  renders  this  ash  particularly  rich  in  alkaline  salts. 
It  is  sowed  by  hand,  in  the  spring,  upon  clover,  and  the  following 
year  an  abundant  crop  of  wheat  is  obtained.  The  same  material  is 
also  used  in  the  cultivation  of  the  hop  ;  and  it  is  said  that,  administer- 
ed in  small  quantity  to  the  roots  of  the  vine,  they  preserve  the  plant 
from  the  attacks  of  destructive  insects. 

Coal-ashes.  Coal,  like  the  two  last  combustible  materials,  is  the 
product  of  vegetables,  which,  however,  have  undergone  such  a 
change  as  to  have  lost  almost  every  trace  of  organization.  Coal  of 
different  kinds  contains  from  1.4  to  about  2.3  per  cent,  of  ashes,  and 


816  ALKALINE  SALTS. 

about  2  per  cent,  of  azote.      The  ash  of  a  variety  of  coal  of  verjf 
excellent  quality  gave  of — 

Argillaceous  matter  (silica"?)  not  soltble  in  acids  69 

Alumina 5 

Lime 9 

Magnesia 8 

Oxide  of  manganese 3 

Oxide  and  sulpliuret  of  iron 16 

100 
Coal  ash  also  contains  very  minute  quantities  of  alkaline  salts, 
which  usually  escape  analysis  when  they  are  not  especially  inquired 
after.  One  specimen  analyzed  in  my  laboratory,  gave  nearly  00.1 
of  alkali.  Coal-ash  is  particularly  useful  on  clayey  soils ;  it  acts  by 
lessening  the  tenacity  of  the  soil ;  and  further,  doubtless,  by  the  in- 
troduction of  certain  useful  principles,  such  as  lime  and  alkaline  salts. 

OF  ALKALINE  SALTS. 

It  is  impossible  to  doubt  that  salts  having  potash  and  soda  for  their 
base  are  useful  in  agriculture.  The  influence  of  u^ood-ashes,  and  of 
paring  and  burning  is  unquestionable  ;  and  they  are  so,  in  some  con- 
siderable degree  at  least,  in  consequence  of  the  salts  of  these  bases 
which  they  supply,  and  which  always  enter  into  the  constitution  of 
vegetables.  There  are  even  certain  crops  which,  in  order  to  thrive, 
require  a  particular  alkali ;  the  vine,  for  example,  the  fruit  of  which 
contains  bitartrate  of  potash,  and  sorrel,  which  contains  the  binoxa- 
late  of  the  same  base,  must  needs  have  supplies  of  potash.  The 
plants  which  are  grown  for  the  production  of  soda,  the  salsola,  <5fC., 
from  which  barilla  is  made,  must  come  in  a  soil  that  naturally  con- 
tains a  salt  of  soda,  such  as  that  of  the  sea-shore. 

It  would  appear,  however,  that  the  salts  of  soda  or  potash,  must 
not  exceed  a  very  small  proportion  in  the  soil.  All  the  experiments 
that  have  yet  been  undertaken  with  a  view  to  ascertain  the  action 
of  different  saline  substances  on  growing  vegetables,  have  led  to  no 
very  certain  conclusion  but  this,  that  they  must  be  used  very  sparing- 
ly. M.  Lecoq  has  published  an  account  of  some  experiments,  made 
apparently  with  great  care,  which  go  to  prove  that  common  salt,  in 
the  dose  of  from  \\  to  2j  cwts.  per  acre,  favored  the  growth  of  barley, 
wheat,  lucern,  and  flax.  Chloride  of  calcium  and  sulphate  of  soda, 
he  also  found  to  have  the  same  good  effects.  M.  de  Dombasle,  how- 
ever, came  to  conclusions  totally  opposed  to  them,  with  reference 
especially  to  common  salt,  which,  applied  in  the  doses  advised  by  M. 
Lecoq,  was  not  found  to  produce  any  sensible  effeci.  M.  Puvis  also 
obtained  results  that  were  equally  negative.  It  would  perhaps  have 
been  well  had  M.  Lecoq  begun  by  determining  the  proportion  of 
alkaline  salts  which  existed  previously  in  the  soil  on  which  he 
conducted  his  experiments.  If  he  operated  on  a  soil  that  was  either 
destitute  of  these  salts,  or  that  contained  them  only  in  minimum 
proportion,  very  probably  he  did  good  by  adding  them. 

Nitrate  of  potash  has  been  repeatedly  recommended  ?r  an  agent 
useful  in  agriculture.  The  conclusions  that  have  been  come  to 
however,  from  its  use,  are  far  from  accordant.     In  the  processta 


NITHATE  OF  SODA.  81 

or  modes  of  using-  nitre  to  the  soil,  it  is  not  uncommon  to  find  il 
associated  with  soot,  or  with  vegetable  mould,  substances  which 
require  no  assistance  of  any  kind  to  constitute  them  powerful 
manures,  and  the  addition  of  which  is  therefore  calculated  to  raise 
strong  doubts  of  the  advantageous  qualities  ascribed  to  nitre  alone. 
Were  the  advantages  of  nitrate  of  potash  much  less  questioned 
than  they  are,  however,  the  high  price  of  the  salt  would  probably 
always  oppose  insuperable  obstacles  to  its  employment.  This  is 
the  reason,  in  all  likelihood  that  has  turned  the  attention  of  Eng- 
lish agriculturists,  for  several  years  past,  to  nitrate  of  soda,  a  salt 
that  is  imported  in  quantity  from  Peru,  and  of  which  the  price 
per  cwt.  may  be  about  forty  shillings ;  a  price  which,  were  it  found 
really  useful,  would  permit  of  its  being  used.  Admitting  the  ac- 
curacy of  the  experiments  that  have  been  made,  indeed,  we  can- 
not doubt  the  efficacy  of  nitrate  of  soda  on  soil  already  furnished 
with  organic  manure.  The  quantity  that  has  been  recommended 
is  about  one  cwt.  per  acre. 

Mr.  Barclay  made  a  few  experiments  after  having  heard  muph  of 
the  nitrate  of  soda  from  his  neighbors,  of  the  results  of  which  the 
following  examples  will  suffice  to  give  a  comparative  estimate  : 

Without  nitrate.  With  nitrate.  Difference  in  favor  of 

the  nitrates. 

Wheat 31  bush.  2  pecks.  35  bush.  3  pecks.  5  bush.  3  pecks. 

Straw 21  cwt.  0  qrs.  19  lbs.     23  cwt.  2  qrs.  26  lbs.     3  cwt.  2  qrs.  7  lbs. 

The  produce  of  the  land  treated  with  nitrate,  however,  did  not 
fetch  so  high  a  price  at  market  as  that  grown  without  it ;  and  every 
item  of  expense  taken  into  the  reckoning,  the  use  of  the  nitrate  was 
attended  with  no  commercial  benefit.  Still  this  does  not  militate 
against  the  fact,  that  the  production  of  vegetable  matter  was  in- 
creased upon  land  treated  with  the  nitrate  of  soda.  And  indeed 
much  of  the  information  which  M.  de  Gourcy  collected  in  England, 
is  of  a  kind  that  tends  to  confirm  the  favorable  influence  of  this  salt 
on  vegetation.  Wheat,  clover,  and  Swedish  turnips  are  particular- 
ly specified  as  benefiting  from  its  use.  These  facts  admitted,  we 
rnay  ask  :  how  does  the  nitrate  of  soda  act  ?  The  chemical  consti- 
tution of  the  nitrates  is  such,  that  we  might  conceive  their  acting  at 
once  as  mineral  and  as  organic  manures.  The  important  point  for 
solution  was  to  ascertain  whether  the  azote  of  the  nitrate  contribu- 
ted in  any  way  to  the  formation  of  the  azotized  principles  of  plants. 
Davy,  in  taking  with  much  distrust  the  report  of  Sir  Kenelm  Digby's 
experiments  on  the  influence  of  nitre  in  the  cultivation  of  barley, 
shows  no  disinclination  to  believe  that  the  azote  of  the  salt  may 
concur  in  the  production  of  albumen  and  gluten.*  This,  however, 
is  a  point  in  physiology  which  may  be  put  to  the  proof  by  experi- 
ment, and  seems  peculiarly  worthy  of  being  tested  in  this  way.  I 
have  admitted  it  as  extremely  probable,  that  the  azote  of  the  azoti- 
zed principles  of  plants  has  its  source  either  in  the  ammonia,  which 
18  the  special  iltimate  product  of  the  organic  manure  we  employ,  ox 

-  -.  Agricultural  Chemistry 

•27* 


819  MANURE — &i?SUM. 

in  the  azote  of  the  atmosphere,  or  in  both  simultaneously ;  b  it  the 
opinion  which  should  maintain  that  the  ammonia  derived  from  the 
organic  constituents  of  the  soil,  passes  into  the  state  of  nitric  acid 
before  penetrating  the  tissues  of  plants,  would  find  support  nearly  in 
the  same  facts  which  I  have  quoted  as  favoring  the  former  view. 
We  have  seen,  moreover,  in  our  general  considerations  on  nitrifica- 
tion, with  what  facility  the  azote  of  ammonia  undergoes  acidification 
in  certain  circumstances,  a  fact  from  which  an  argument  of  much 
potency  for  the  nitric  acid  theory  naturally  flows.  I  shall  here  add 
an  observation  to  which  I  have,  up  to  this  time  perhaps,  attached 
too  little  importance.  When  M.  Rivero  and  I  examined  the  hig:  ly 
irritating  and  poisonous  milky  sap  of  the  hura  crepitans,  we  had  oc 
casion  to  leave  a  considerable  quantity  of  the  water  derived  from 
the  sap,  after  separating  the  caseum,  to  itself;  by  the  spontaneous 
evaporation  of  this  vi'ater,  we  collected  really  a  considerable  quanti- 
ty of  nitrate  of  potash.  Since  this  time  I  have  had  occasion  to 
note  the  same  salt  in  the  sap  of  several  trees  of  the  tropics.  In  the 
leaves  and  fruit,  however,  I  have  never  found  more  than  very  minute 
qu^l.cities. 

Gypsum,  sulphate  of  lime,  or  pla^ier  of  Parts,  is  a  compcjnd  of 
41.5  lime  with  58.5  sulpnuric  acid;  gypsum  generally  contains  a 
quantity  of  constitutional  water,  in  which  case  it  consists  of  79.2 
sulphate  of  lime,  and  20.8  water  =  100.  This  hydrate  of  sulphate 
of  lime  is  one  of  the  abundant  minerals  on  the  surface  of  the  earth  ; 
it  is  met  with  in  the  crystalline  state,  and  in  granular  and  fibrous 
masses  in  the  strata  of  most  recent  formation.  It  has  no  sensible 
taste,  but  is  slightly  soluble  in  water,  this  fluid  dissolving  ^  of  its 
weight  of  the  salt.  Exposed  for  some  time  to  a  white  heat,  it  loses 
its  water  of  constitution,  and  passes  into  the  state  in  which  when 
ground  it  is  known  under  the  name  of  plaster  of  Paris. 

Gypsum  is  one  of  the  most  commonly  employed  of  the  mineral 
manures.  Its  virtues  appear  not  to  have  been  unknown  to  the  an- 
cients :  but  until  lately  its  employment  was  limited  to  a  few  circum- 
scribed districts.  It  was  only  about  the  middle  of  the  eighteenth 
century  that  the  protestant  pastor,  Mayer,  took  up  the  study  of  gyp- 
sum in  the  principality  of  Hohenlohe,  proceeding  upon  certain  in- 
formation which  he  had  obtained  from  Hehlen  of  Hanover,  in  the 
neighborhood  of  which,  it  was  employed  as  an  improver. 

By  extending  a  knowledge  of  the  virtues  of  gypsum,  both  by  his 
example  ard  his  writings,  Mayer  did  great  service  to  agriculture. 
Experiments  were  soon  instituted  in  all  quarters.  Tschiffeli  in 
Switzerland,  Schubart  in  Germany,  and  Franklin  in  America,  wrote 
on  its  effects,  or  practically  demonstrnted  them  to  the  satisfaction  of 
all.  But  it  appears  to  be  the  fate  c  "  all  useful  discoveries,  of  all 
happy  applications  of  principles,  to  be  opposed  at  first,  and  only  to  be 
admitted  after  having  been  vainly  disputed.  The  use  of  gypsum 
soon  aroused  formidable  opposition  ;  and  there  is  a  curious  episodf 
in  the  history  of  the  paper  war  that  was  long  carried  on  upon  hi 
•ubject,  which  I  think  worth  noting.  Among  the  most  strenuous 
•oemies  of  the  use  of  gypsum,  were  the  proprietors  of  the  saJt-paiUb 


GYPSUM.  319 

They  declared  that  gypsum  was  not  only  incompetent  to  replace 
schlot  or  the  refuse  of  their  pans,  as  had  been  proposed,  but  that  it 
was  injurious ;  schlot  was  the  only  veal  improver,  the  stimulant  of 
stimulants,  for  which  there  was  no  substitute.  But  it  turned  out  by 
and  by,  that  the  schlot  oi  the  salt-pan  was  found  to  be  neither  more 
nor  less  than  sulphate  of  lime,  than  gypsum — the  article  that  was 
not  only  inefficient,  but  injurious.  These  gentlemen  were  afraid 
that  the  use  of  gypsum  extending,  they  would  want  a  market  for 
their  refuse. 

The  use  of  gypsum  once  introduced,  extended  rapidly  in  France, 
particularly  around  Paris,  whence  it  crossed  the  Atlantic,  and  the 
fields  of  North  America  were  actually  manured  with  the  produce  of 
the  quarries  of  Montmartre.  The  lately  cleared  lands  of  America 
abound  in  humus,  and  the  plants  indigenous  there  were  most  bene- 
ficially acted  on  by  gypsum,  which  really  produced  remarkable 
effects ;  in  both  the  new  and  the  old  world,  its  power,  as  one  of  the 
most  useful  auxiliaries  of  vegetation,  soon  appeared  to  be  estab- 
lished. 

We  must  not  blind  ourselves  to  the  fact,  however,  that  the  parti- 
sans of  gypsum  were  guilty  of  exaggeration.  They  spoke  of  the 
substance  as  a  universal  manure,  capable  of  supplying  the  place  of 
every  other,  as  advantageous  for  every  description  of  crop,  as  appli 
cable  to  every  variety  of  soil.  Experience  soon  set  bounds  to  sucl 
indiscriminate  laudation  ;  it  was  found  that  gypsum  alone  was  inad- 
equate to  produce  fertility,  that  it  always  required  the  concurrence 
of  organic  manures,  if  the  soil  did  not  contain  them  of  itself;  that 
it  only  acted  beneficially  on  a  certain,  and  that  a  very  small  number 
of  plants ;  lastly,  that  it  was  upon  artificial  meadows,  constituted  by 
clover,  lucern,  and  sainfoin,  that  it  produced  its  best  effects  ;  its 
action,  on  the  contrary,  being  scarcely  perceptible  upon  natural  mead- 
ows, doubtful  in  connection  with  hoed  crops,  and  null  with  the  cereals. 
These  negative  results  cannot  be  called  in  question  ;  they  were  come 
to  by  parties  who  were  every  way  interested  in  having  the  decision 
otherwise. 

The  best  season  for  spreading  gypsum  is  the  spring,  and  when  the 
clover,  sainfoin,  or  lucern,  has  already  made  a  certain  degree  of 
progress  ;  calm  and  moist  weather  is  the  best  for  laying  it  on. 
Opinion  wa»  long  divided  as  to  whether  it  should  be  applied  in  its 
natural  state,  and  simply  ground,  or  first  burned  and  then  ground. 
But  it  is  now  generally  admitted  that  burning  adds  nothing  to  the 
qualities  of  gypsum.  Although  the  usual  practice  is  to  sow  or  pow- 
der the  meadows  with  the  ground  gypsum,  it  is  still  acknowledged 
that  good  effects  are  obtained  from  incorporating  the  substance  with 
the  soil.  The  advantage  of  the  practice  of  scattering  it  on  in  pow- 
der, so  as  to  adhere  to  the  wet  leaves  of  the  growing  plants,  I  find 
explained  in  the  equality  of  distribution  which  is  by  this  means 
effected. 

In  some  places,  the  number  and  extent  of  which  are  by  no  means 
inconsiderable,  no  good  effect  whatever  has  attended  the  application 
of  gypsum,  altho'igh  it  has  been  administered  in  favorable  conditions, 


320  GYPSUM. 

and  in  connection  with  crops  that  elsewhere  derive  the  highest  amovinl 
of  advantage  from  its  use.  This  anomaly  has  been  explained  by 
assuming,  without  proving  experimentally,  however,  that  the  fact  ia 
so,  that  the  soil  in  these  districts  naturally  contains  a  sufficient  dose 
of  gypsum.  It  has  also  been  said  that  gypsum  produces  no  effect  on 
low-lying  and  damp  soils. 

The  quantity  of  gypsum  employed  in  different  places,  varies  great- 
ly :  from  li  to  16  cwts.  per  acre  have  been  recommended.  The 
quality  of  the  article  employed  has  a  great  influence  on  this  question, 
to  say  nothing  of  the  price,  which  in  many  places  is  high. 

The  opinions  of  practical  men,  with  regard  to  the  advantages  and 
propriety  of  applying  gypsum,  although  they  agreed  in  certain  de- 
terminate circumstances,  were  still  far  from  being  unanimous  upon 
every  point.  A  particular  inquiry  into  the  subject  was  therefore 
held  worthy  of  its  attention  by  the  French  government,  and  a  com- 
prehensive report  on  all  the  information  collected,  was  made  by  M. 
Bosc  to  the  Royal  Central  Agricultural  Society  of  France.  This 
report  shows  in  a  striking  manner  the  advantage  that  may  be  deriv- 
ed from  the  lights  of  practical  men ;  in  a  single  line  or  sentence  wo 
frequently  find  a  summary  of  twenty  or  thirty  years  of  experience. 
It  is,  however,  indispensable  to  go  to  these  gentlemen  for  their  in- 
formation ;  the  agriculturists  who  devote  themselves  to  cultivation, 
it  is  notorious,  write  very  little,  and  those  who  spend  very  little 
time  in  this  way,  on  the  contrary,  write  a  great  deal.  It  may  be 
that  the  reason  for  the  silence  of  the  one,  is  that  also  for  the  elo- 
quence of  the  other. 

The  following  series  of  questions  and  answers  I  believe  to  em- 
brace most  of  the  points  connected  with  the  employment  of  gypsum, 
that  are  of  interest. 

1st.  Does  plaster  act  favorably  on  artificial  meadows?  Of  43 
opinions  given,  40  are  in  the  affirmative  ;  3  in  the  negative. 

2d.  Does  it  act  favorably  on  artificial  meadows,  the  soil  of  which 
is  very  damp?     Unanimously,  no.     Ten  opinions  given. 

3d.  Will  it  supply  the  place  of  organic  manure,  or  of  vegetable 
mould  1  i.  e.  will  a  barren  soil  be  converted  into  a  fertile  one  by  the 
use  of  plaster  ?     No,  unanimously.     Seven  opinions  given. 

4th.  Does  gypsing  sensibly  increase  the  crops  of  the  cereals'?  Of 
32  opinions,  30  negative,  2  affirmative. 

The  information  thus  obtained,  valuable  as  it  is,  cannot  yet  be  held 
to  embrace  every  thing  that  seems  desirable.  Happily,  all  that  was 
wanting  has  been  supplied  by  the  individual  inquiries  of  Mr.  Smith 
in  England,  and  of  M.  de  ViMle  in  France. 

The  soil  upon  which  Mr.  Smith  made  his  experiments  was  light, 
with  a  substrate  of  chalk  ;  the  vegetable  earth  was  a  yard  in  depth 
at  the  top  of  the  field,  and  lessened  gradually,  in  such  a  way  that  at 
bottom  it  was  but  three  inches  thick.  Every  precaution  was  taken 
that  the  respective  breadths  contrasted  should  be  as  nearly  as  possi- 
ble in  the  same  circumstances.  The  following  table  shows  the 
teeulta : 


GTPSUM. 


321 


GROWTH    OP    SAINFOIN   UPON    SOILS   GYPSED   AND   UNGTPSED   IN 

1792,  1793,  AND  1794. 


Crop  on  the  deeper  ungypsed 
soil 

Crop  upon  the  contiguous  breadth, 
which  had  received  about  15 
bushels  of  gypsum  in  April, 
1794.       .         .         .         .         . 


Bemarks. 


Difference  in  favor  of  the  gypsed 
breadth  .         .         .         . 

Crop  upon  the  same  soil,  of  less 
depth,  and  not  gypsed     . 

Crop  on  contiguous  soil,  dressed 
with  about  15  bushels  of  gyp- 
sum in  April,  1792  . 

Difference  in  favor  of  the  gypsed 
breadth    .... 


Crop  on  the  same  soil,  3  inches 
deep,  and  not  gypsed 

Crop  on  contiguous  soil,  dressed 
with  about  15  bushels  of  gyp- 
sum, 17th  May,  1794      . 

Difference  in  favor  of  the  gyp- 
sed piece  .... 

Crop  on  the  contiguous  soil  of 
experiment.  No.  3,  gypsed 
with  the  same  dose  in  May, 
1792       .... 

Difference  in  favor  of  the  crop 
gypsed  twice,  at  an  interval  of 
two  years 


Dry 

herb 
p«r  acre. 


Seed  per 
acre. 


lbs. 
3357 

5462 


2105 
2766 

4381 


1615 
2068 

4879 


2811 


4310 


2242 


lbs. 

419 
582 


163 
245 

379 


134 
66 

211 


145 


205 


139 


Weight 

of  total 

crop. 


lbs. 
3776 

6044 


Proportion  of 

stalk  to 

seed. 


2268 
3011 

4760 


1749 
2134 

5090 


2956 


4515 


2381 


100 :  12.5 


100 :  10.7 


100:8.9 


100 : 8.7 


100 : 3.2 


100 : 4.3 


100 : 4.8 


^22 


GTPSUJI. 


These  results  show  to  what  extent  gypsum  is  favorable  t<s  tfcfi 
production  of  sainfoin.  The  cro .  from  the  unplastered  breadth  be- 
ing taken  as  100,  that  upon  the  plastered  breadth  is  231  ;  it  is  more 
than  doubled.  The  influence  of  gypsum  was  also  found  by  Smith 
to  extend  to  grain  ;  assuming  the  grain  crops  on  the  ungypsed  land 
at  100,  those  on  the  gypsed  soil  were  192  ;  they  were  nearly  doubled. 

On  comparing  the  weight  of  the  herbaceous  portion  of  the  sain- 
foin to  that  of  the  seed  produced,  widely  different  relations  are  ap- 
parent. These  Mr.  ^mith  attributed  to  the  different  depths  of  the 
vegetable  soil  in  different  parts  of  the  field.  In  the  first  experiment, 
where  the  relative  proportion  of  seed  is  highest,  the  arable  soil  was 
three  feet  in  thickness  ;  the  other  crops  were  taken  from  parts  where 
the  depth  of  vegetable  mould  was  considerably  less.  Thus  the 
gypsed  soil  produced  at  the  rate  per  acre  : 

cwts.    qrs.      lbs. 

In  the  first  experiment  of         5       0        22  the  depth  of  soil  being  3  feet. 
In  the  second  experiment  of    3        1        15  "  "         18  inches. 

In  the  third  experiment  of       1        3        15  "  "  3  inches. 

With  this  interesting  fact  before  him,  Mr.  Smith  imagined  that 
soils  of  little  depth  wanted  some  principle  essential  to  fructification, 
which  gypsum,  in  spite  of  the  unquestionable  assistance  it  gives,  is 
yet  incompetent  to  supply.  This  principle  is  in  all  probability  or- 
ganic matter,  which  is  naturally  more  abundant  in  the  layer  of  true 
vegetable  mould  which  is  deepest. 

Mr.  Smith's  observations  on  white  clover  were  quite  as  decisive 
in  favor  of  gypsum  as  those  on  sainfoin,  and  are  confirmatory  of  the 
conclusions  of  the  generality  of  farmers  on  the  subject.  The  gyp- 
sum in  connection  with  this  crop  was  applied  in  the  dose  of  6  bush- 
els per  acre,  on  the  22d  of  May,  a  date  at  which  the  clover  looked 
pale,  and  seemed  to  want  sap.  A  fortnight  afterwards,  the  effects 
of  the  gypsum  were  obvious;  although  no  rain  had  fallen  in  the  in 
terval,  the  clover  had  become  vigorous,  and  soon  formed  a  covering 
thick  enough  to  protect  the  ground  from  the  scorching  rays  of  the 
sun,  which  burned  up  all  the  parts  which  had  not  been  gypsed. 


COMPARATIVE    GROWTHS    OF  WHITE    CLOVER,  GYPSED    AND    UNGYPSED, 
BY    MR.    SMITH. 


1 

EXPERIMENTS. 

Herb  or 

stalk  per 

acre. 

Seed 
per  acre. 

Total 
weight  of 
the  crop. 

Proportion 

of  herb  to 

seed. 

A.  Gypsed      .          .     . 

A.  Not  gypsed         .     . 

Difference            .     . 

B.  Gypsed           ... 
B.  Not  gypsed    .     .     . 

Difference       .     .     . 

lbs. 

2226 

839 

lbs. 

316 

56 

lbs. 
2542 

895 

100:   14.3 
100:     6.7 

K)0:     7  6 
100:     7.0 

1387 

2270 
500 

260 

174 

61 

1647 

2444 
561 

1770 

113 

1883 

GTPSTTM. 


323 


The  mean  o'  chese  two  experiments  shows  that  the  crop  of  white 
clover  on  the  ungypsed  land  being  100,  that  on  the  gypsed  is  225 — 
twice  and  a  quarter  more. 

The  experiments  of  M.  de  Villele  m^y  be  viewed  as  supplemen 
Jary  or  complementary  to  those  of  Mr.  Smith.  They  were  per- 
formed in  the  south  of  France,  in  accordance  with  the  routine  that 
is  generally  followed,  viz  :  clover-hay,  or  sainfoin,  previous  to  grain, 
upon  soils  of  considerably  different  nature,  and  with  doses  of  gyp- 
sum that  varied  from  8  to  3  on  the  same  extent  of  surface.  His 
conclusions  or  crops  are  stated  in  the  following  table  : 


KINB  OP 
SOIL. 


Light,  dry,  ex- 
posed to  the 
Bouth,  6  to  9 
inches  deep, 
and  on  cliallc. 
1 

Stony  clayey,  A 
moist,  about  I 
16  inch. deep  f 
on  a  stiff  clay.  J 


Crop. 


Sainfoin 
Sainfoin 
Sainfoin 


Clover 
Clover 


Gyp- 
sum 
per 
acre. 


wt.qr, 
6  3 
2  2 
4    4 


40  3  19 
32  2  27 


Dry  crop 
on  mea- 
dow not 
gypsed, 
per  acre. 


Excess  of  ®  *     I  2  g 

O-      S  o  ??  o  c  S 


cwt.qr.lbs. 
18  0    1 

16  1  13 

17  0  21 


20  1  23 
19  2  16 


over  the 
crop  not 
gypsed. 


cwt.qr.lbs 

10  2  15 
16  1  13 
19  3   8 


20  1  23 
13  0  11 


«.   d. 

17  7 
27  1 
3 


33  10 

21    8 


Hi 


o  <u 

PM7 


10  10 
25  0 
11 


2    3 
14    2 


The  unquestionable  fact  of  a  mineral  salt  stimulating  the  growth 
of  certain  plants  in  so  remarkable  a  manner  as  to  double  and  even 
to  triple  the  usual  quantities  grown  per  acre,  naturally  aroused  the 
curiosity  of  mankind  to  inquire  into  and  endeavor  to  discover  the 
cause.  Explanations  in  abundance  have  been  proposed  ;  but  so  lit- 
tle satisfactory  in  general,  that  I  do  not  think  myself  bound  to  men- 
tion them  all.  I  shall  limit  myself,  indeed,  to  two ;  one  proposer! 
by  Davy  some  time  ago,  and  one  advocated  by  Liebig  very  lately. 

Davy  assumes  that  the  plants  of  artificial  meadows  simply  absorb 
sulphate  of  lime.  He  assures  us  that  he  had  found  a  large  propor- 
tion of  this  salt  in  the  ashes  of  vegetables  grown  in  soil  which  had 
been  treated  with  turf  ashes  abounding  in  the  substance.  He  be- 
lieved that  the  gypsum  entered  particularly  into  the  constitution  of 
the  woody  fibre.  And  it  is  not  uninteresting  to  observe,  that  the 
plants  which  gypsum  certainly  favors  in  the  highest  degree,  are  of 
very  rapid  growth ;  and  that  in  all  probability  they  would  find  it 
difficult  to  obtain  the  whole  of  the  sulphate  of  lime  they  require  from 
ordinary  or  ungypsed  soils  within  the  period  of  their  growth.  Let 
it  not  be  forgotten,  however,  that  if  it  be  true  that  saline  substances 
are  indispensable  to  the  organization  of  plants,  it  is  also  true  that 
these  substances  can  only  be  absorbed  within  certain  limits  ;  a  salt 
the  best  calculated  by  its  nature  to  aid  vegetation,  would  become  in- 
jurious by  its  excessive  proportion,  did  the  water  which  moistened 
the  general  soil  contain  too  large  a  proportion  of  it  in  solution :  if  a 
plant  languishes  when  it  has  sot  enough  of  one  or  other  of  its  natu- 
ral saline  constituents,  it  also  dies  when  furnished  with  the  sam* 
iubstance  in  excuss. 


il|4  GTPSUM. 

Let  us  now  remember  that  salts  can  osly  act  on  ve^evables  in  the 
Btate  of  solution,  and  we  shall  understand  how  those  only  which  are 
but  sparingly  soluble,  can  ever  be  advantageously  employed  in  agri- 
culture. Water,  in  fact,  having  the  power  to  dissolve  only  a  very 
limited  quantity  of  the  mineral  manure,  will  present  it  to  the  grow- 
ing plant  nearly  in  a  constant  quantity,  so  long  as  the  soil  contains 
any  fair  proportion  of  the  substance.  It  is  in  this  way  precisely 
that  gypsum  appears  to  gain  its  superiority  over  the  generality  of 
mineral  or  saline  manures  ;  water  does  not  take  up  more  than  j^T^th 
part  of  its  weight  before  it  becomes  saturated  ;  a  certain  proportion 
of  the  moisture  of  the  earth  being  dissipated  by  evaporation,  there 
is  forthwith  a  precipitation  of  sulphate  of  lime ;  but  the  moisture 
that  remains  is  nevertheless  charged  as  before,  neither  more  nor  less, 
and  in  the  fittest  state,  as  it  seems,  to  administer  to  the  wants  of  the 
growing  plant.  If  instead  of  sulphate  of  lime  we  suppose  some  salt 
that  is  much  more  soluble,  sulphate  of  soda  for  example,  we  have 
nothing  of  the  same  state  of  equilibrium  between  the  quantity  of 
moisture  and  its  charge  of  saline  ingredients  maintained.  Suppos- 
ing the  moisture  of  the  ground  to  hold  ^^^^h  of  sulphate  of  soda  in 
solution,  and  this  quantity  calculated  to  produce  good  effects  upon 
growing  vegetables  :  suppose  now  that  a  drought  sets  in,  which  by 
dissipatmg  one-half  of  the  moisture,  increases  the  charge  of  saline 
matter  to  3  jo^b  of  its  bulk,  it  may  very  well  happen  that  this  pro- 
portion, instead  of  proving  beneficial,  will  be  felt  as  injurious  to  vege- 
tation. 

The  hypothesis  of  Davy,  supported  by  these  ingenious  views  of 
M.  Chaptal,  would  therefore  lead  us  to  regard  gypsum  as  behaving 
to  plants  in  the  same  general  way  as  the  insoluble  salts  which  usual- 
ly form  an  element  of  the  soil  or  of  manures,  the  phosphate  and  car- 
bonate of  lime,  in  particular,  salts  which  are  made  apt  to  enter  the 
tissues  of  plants  by  the  carbonic  acid  which  is  found  in  all  the  water 
that  falls  from  the  clouds  and  that  moistens  the  soil,  and  which  has 
the  property  of  dissolving  small  quantities  of  them.  But  while  the 
str  .ngth  of  these  solutions,  weak  at  all  times,  is  liable  through  at- 
mospherical vicissitudes  to  vary,  when  the  mere  traces  of  saline 
matter  which  at  best  they  offer  at  any  time  are  inadequate  to  meet 
the  demands  of  a  crop  disposed  to  grow  rapidly  and  luxuriantly, 
such  as  clover,  sainfoin,  andlucern,  the  solution  of  sulphate  of  lime, 
of  the  same  strength  at  all  times  and  under  all  circumstances,  is 
ready  to  supply  the  plants  with  the  mineral  substance  they  require, 
however  rapid  and  vigorous  their  growth. 

The  theory  of  the  action  of  gypsum  proposed  by  Professor  Liebig 
is  extremely  ingenious.  He  admits,  with  M.  de  Saussure,  the  pre- 
sence of  carbonate  of  ammonia  in  the  atmosphere,  and  consequently 
in  rain-water.  This  fact  established,  and  it  appears  undeniable,  the 
infiuence  of  gypsum  would  consist  in  its  faculty  of  fixing  the  infinite- 
ly small  quantity  of  carbonate  of  ammonia  which  is  brought  down 
by  the  rain  and  the  dew,  and  so  preventing  its  dissipation  on  the 
return  of  drought  and  sunshine.  Carbonate  of  ammonia,  in  fact,  as 
•"•^  hare  alreadyspen,  when  speaking-  of  manures,  in  contact  witb 


GYPSUM.  323 

the  sulphate  of  lime  decomposes  this  salt,  carbonate  of  lime  and 
sulphate  of  amiri'DTAi  being  formed.  I  shall  by  and  by  inquire 
whether  the  reaction  that  takes  place  is  of  the  precise  nature  of  that 
here  stated  ;  but  admitting,  for  the  present,  that  it  is,  it  would  still 
be  comp<;tent  for  us  to  ask  if  the  quantity  of  ammonia  condensed  in 
this  way  was  likely  to  suffice  for  the  production  of  such  decided  ef- 
fects as  we  frequently  witness  in  connection  with  the  crops  that  are 
assisted  by  gypsum. 

Professor  Liebig  observes  that  a  pound  of  sulphate  of  lime  once 
converted  into  sulphate  of  ammonia,  would  introduce  into  the  soil  a 
quantity  of  ammonia  equivalent  to  that  which  would  be  afforded  it 
by  6.250  lbs.  of  horse's  urine  ;  a  showing  upon  which  it  would  be 
easy  to  demonstrate,  taking  the  composition  of  sainfoin  to  be  as  I 
have  sho'vn  it,  that  a  pound  of  plaster  fertilizing  the  ground  to  this 
extent,  would  be  adequate  to  increase  one  hundred-fold  the  quantity 
of  dry  fodder  produced. 

According  to  my  manner  of  viewing  this  question,  it  must  be  ex- 
amined on  a  totally  different  basis.  It  is  certain,  for  instance,  that 
gypsum  has  no  effect  upon  natural  meadows  ;  positive  experience 
has  satisfied  me  of  the  absolute  inutility  of  the  substance  here  ;  so 
that  upon  my  natural  meadows  at  Bechelbronn,  I  now  never  employ 
a  particle  of  it.  But  let  us  review  Professor  Liebig's  theory  in  con- 
nection with  the  production  of  sainfoin  and  clover,  which  in  a  gene- 
ral way  derive  an  advantage  from  gypsum,  which  no  one  disputes. 

Our  harvest  of  clover,  taken  as  dry,  amounts  on  an  average  from 
strongly  gypsed  land,  to  2  tons  1  cwt.  very  nearly  per  acre  ;  and 
this  quantity  agrees  pretty  well  with  that  which  appears  common  in 
Germany.  It  is  generally  allowed  that  by  gypsing  we  double  the 
produce.  It  would  follow  from  this,  that  an  acre  which  had  not 
been  gypsed,  would  yield  no  more  than  20|  cwts.  of  dry  clover ;  in 
my  opinion  the  reduction  would  be  still  greater.  Dry  clover  hay, 
made  from  the  plant  cut  when  in  flower,  contains  about  2  per  cent, 
of  azote.  The  20|  cwts.  of  forage  gained  by  the  intervention  of  the 
gypsum  would  consequently  contain  110  lbs.  of  ammonia,  equivalent 
to  134.2  lbs.  carbonate  of  ammonia.  This  consequently  is  the  quan- 
tity of  carbonate  of  ammonia  which  the  gypsum  ought  to  have  been 
the  means  of  procuring  from  the  rain  which  falls  upon  an  acre  of 
land  during  the  time  that  clover  is  upon  the  ground,  in  order  to  fur- 
nish the  azote  contained  in  the  increased  quantity  of  the  crop. 

Now  in  Alsace,  from  the  time  of  gypsing  in  April,  to  the  time  of 
mowing  in  July,  there  falls  on  an  average  3.92,  nearly  4  inches  of 
rain,  which  would  amount  in  round  numbers  to  982  tons  per  acre. 
Were  the  azote  of  what  may  be  spoken  of  as  the  surplus  produce, 
derived  from  the  rain  in  fact,  all  the  water  that  falls  ought  to  contain 
j^l^  of  its  weight  of  carbonate  of  ammonia.  It  is  very  question- 
able, however,  whether  any  such  proportion  of  ammoniacal  salts 
exist  in  rain-water  ;  yet  the  proportion  ought  to  be  very  much  great- 
er, inasmuch  as  we  have  supposed  the  whole  of  the  rain  that  fell  to 
penetrate  the  ground,  none  of  it  to  run  off;  but  the  truth  is,  that  a 
very  considerable  proportion  of  the  rain  that  falls  never  sinks  into 

26 


Jo  GYPSUM. 

the  soil ;  once  the  surface  is  thoroughly  soaked,  much  that  falls 
drains  off,  passes  away  by  tlie  ditches,  and  is  lost  with  all  it  may 
contain  that  would  prove  beneficial  to  vegetation.  It  is  iii  fact  alto- 
gether impossible  to  make  any  approximation,  even  of  the  roughest 
kind,  in  regard  to  the  quantity  of  rain-water  that  soaks  into  and  that 
runs  off  the  ground  ;  and  thus  no  kind  of  estimate  can  be  formed  of 
the  relation  between  the  moisture  absorbed  by  plants,  and  that  which 
escapes  direct  by  the  evaporation,  without  passing  through  them  at  all. 

But  even  in  admitting  that  it  was  really  the  ammonia  contained 
in  the  rain-water,  to  which  the  very  considerable  increase  of  the 
crop  of  clover,  lucern,  and  sainfoin  was  owing,  it  would  still  be  left 
for  us  to  explain  wherefore,  meteorological  and  other  circumstances 
remaining  the  same,  the  same  relative  eft'ects  were  not  produced 
upon  natural  meadows  covered  with  grasses,  upon  hoed  crops,  such 
as  beet  and  turnips,  and  upon  wheat ;  finally,  the  most  serious  ob- 
jection that  can  be  urged  against  this  theory  is  founded  upon  the 
fact,  that  gypsum  has  no  truly  beneficial  effect  upon  artificial  mea- 
dows, save  and  except  when  the  soil  to  which  it  is  applied  contains 
an  adequate  proportion  of  azotized  organic  manure.  In  a  moderate- 
ly manured  soil,  gypsum,  as  all  the  world  knows,  produces  no  sen- 
sible improvement ;  and  as  M.  Cvud,  one  of  those  men  wliom  long 
experience  has  placed  at  the  head  of  practical  farming,  said  :  It  is 
to  throw  away  both  money  and  trouble  to  put  gypsum  upon  an  un- 
kindly and  impoverished  bottom.  It  would  seem,  however,  that  if 
gypsum  really  fixes  ammonia  in  the  soil,  in  consequence  of  its  action 
upon  the  rain-water  that  falls,  converting  its  carbonate  into  sulphate 
of  ammonia,  the  ammoniacal  salt  once  introduced  into  the  soil,  ought 
to  act  independently  and  without  the  concurrence  of  another  manure. 
That  it  really  does  act  isolatedly,  and  of  its  own  proper  force  when 
it  exists,  has  been  proved  by  the  experiments  of  M.  Schattenmann, 
who  demonstrated  on  the  large  scale  the  beneficial  effects  of  the 
sulphate  of  ammonia  directly  applied  to  natural  meadows.  It  is 
obvious,  that  if  the  theory  which  I  discuss  be  true,  the  greater  num- 
ber of  practical  observations  which  I  have  quoted  must  necessarily 
be  false ;  or,  on  the  contrary,  these  observations  being  accurate,  the 
theory  must  be  erroneous. 

I  have  given  reasons  for  maintaining  the  accuracy  of  the  practical 
results  ;  nevertheless,  the  better  to  establish  this  conviction,  I  have 
thought  it  advisable  to  add  a  few  facts  to  the  many  that  are  already 
extant.  I  was,  therefore,  induced  to  undertake  a  series  of  experi- 
ments with  a  view  to  study,  independently  of  all  hypothetical  idea, 
the  action  of  gypsum  upon  certain  hoed  crops  and  cereals. 

These  experiments  were  made  upon  patches  of  land  of  440  square 
yards  each.  Every  precaution  was  taken  to  render  the  experiments 
strictly  comparable  one  v^ith  another.  Thus  the  ground  appropri- 
ated to  each  particular  crop  was  divided  into  three  equal  contiguous 
zones.  The  first  zone,  A,  always  received  gypsum  in  the  ratio  of 
4f  bushjls  per  acre.  The  second  zone,  B,  and  the  third  zone,  C 
were  not  gypsed.  Each  zone  was  sowed  with  the  same  quantity  o 
•eed,  or  planted  with  an  equal  number  of  beet  plants  or  potatoea 


MANURE GYPSUM.  327 

A.  and  C  were  the  surfaces  which  I  proposed  to  myself  to  contrast ; 
the  intermediate  zone,  B,  was  a  kind  of  neutral  ground  employed 
merely  to  prevent  the  immediate  contact  of  the  gypsed  with  the  un- 
gypsed  zone.  I  may  here  remark,  that  it  would  be  well  always  to 
take  such  a  precaution  in  making  experiments  on  the  eifects  of  dif- 
ferent manures. 

In  1842  I  tried  the  effect  of  gypsum  upon  wheat  coming  after  three 
different  crops.  1st.  After  clover  ploughed  in.  2d.  After  beet- 
root.    3d.  After  potatoes. 

The  gypsum  was  applied  the  19th  of  May,  at  which  time  the 
wheat  looked  extremely  well.  The  crop  was  cut  betw^een  the  21st 
and  26th  of  July,  and  the  following  are  the  results  obtained  : 

CroTtB  Weiffht  of  grain,  corn,  and  straw. 

^  '  A.  piece  gypsed.    B.  not  gypsed.    C.  not  gypted. 

Wheat  after  clover 319  lbs.  323  lbs.  327  lbs. 

Wheat  after  mangel-wurzel 195    "  176    "  158    " 

Wheat  after  potatoes 235    "  158    "  264    " 

Average  of  the  three  experiments 250    "  248    "  250    " 

The  year  1842  having  been  unfavorable  to  wheat  in  consequence 
of  the  long  drought,  the  experiment  required  to  be  repeated.  This 
was  done  in  1843  ;  and  it  must  be  allowed,  that  an  experiment  could 
scarcely  be  conducted  under  circumstances  of  weather  more  favora- 
ble to  the  cultivation  of  grain  ;  the  results  here  are  given  for  equal 
spaces  of  three  French  acres,  equal  to  385  square  yards.  The  gyp- 
sed zones  had  been  treated  with  70  lbs.  of  sulphate  of  lime  each  : 

Year  1843.  Sheaves.  Grain.        Straw,  chaff,  and  waste. 

lbs.  lbs.  lbs. 

Rye  with  gypsum 516  137  379 

Rye  without 472  127  345 

Wheat  with  gypsum 462  147  315 

Wheat  without 510  156  254 

Wheat  without 453  143  310 

Oats  with  gypsum 329  112  217 

Oats  without...    368  113  255 

From  these  numbers  it  is  obvious  that  gypsum  produces  no  appreci- 
able effect  upon  wheat,  oats,  and  rye,  conclusions  that  agree  with 
those  come  to  in  the  previous  year. 

EXPERIMENT  WITH  FIELD-BEET  OR  MANGEL-WURZEL,  OPENING  THE 
ROTATION  WITH  MANURED  SOIL,  1842. 

The  plants  were  transplanted  and  watercv-l,  and  the  gypsum  was 
applied  at  the  time  of  earthing  up ;  a  good  deal  of  rain  fell,  and 
shortly  after  having  been  laid  on,  he  gypsum  had  become  incorpo- 
rated with  the  ground.  The  crop  vas  gathered  on  the  8th  of  Octo- 
Der,  three  months  after  the  gypsing,  and  from  two  equal  surfaces, 
each  of  242  square  yards  in  extent,  weighed  as  follows  : 

From  the  gypsed  ground 13  cwt.  2  qrs.  6  lbs. 

From  the  ungypsed 12    "      2    "     3    " 

The  gypsum  would  therefore  appear  to  have  had  no  beneficia. 
effect ;  for  the  difference  in  favor  of  the  gypsed  piece  is  so  trilling 


828 


GYPSUM. 


that  it  cannot  be  reasonably  ascribed  to  the  mineral  manure  :  in  fact, 
the  quantity  obtained  from  the  gypsed  surface  does  not  exceed  that 
which  we  constantly  take  from  fields  in  the  ordinary  course  of  cul- 
tivation, and  which  have  received  no  gypsum. 

The  action  of  gypsum,  limited  as  it  is  to  certain  crops,  will  not 
allow  us  to  admit  that  it  produces  its  effect  by  fixing  in  the  ground 
the  carbonate  of  ammonia  contained  in  rain-water  ;  were  it  connect- 
ed with  any  fixation  of  ammonia,  it  would  be  manifested  generally, 
and  not  in  particular  instances  only.  Davy's  theory  therefore  ap- 
pears the  more  plausible,  and  requires  discussion.  Did  the  ashes  of 
the  clover  grown  in  gypsed  soils  actually  contain  a  large  proportion 
of  sulphate  of  lime,  as  affirmed  by  the  illustrious  English  chemist, 
the  action  of  gypsunff  would  be  readily  understood.  The  whole 
question,  therefore,  seems  to  turn  upon  the  composition  of  the  ashes. 

I  have  analyzed  the  ashes  of  clover  grown  at  Bechelbronn,  with- 
out and  with  the  concurrence  of  gypsum.  I  shall  here  give  the 
conclusions  come  to  in  1841,  a  year  remarkable  for  the  heavy  crops 
of  clover,  and  those  also  for  the  year  1842,  when  the  clover  crop 
was  but  indifferent.  The  first  table  contains  the  results  in  the  order 
in  which  they  were  registered  ;  the  second  contains  those  obtained 
after  the  deduction  of  the  carbonic  acid  and  carbon  which  had  re- 
mained in  the  ashes  examined  : 


Carbon  and  Carbonic  acid 
iucluded. 

Extraordinary  Crop  of  1841. 

Unfarorable  Crop  of  1841.         1 

Ashes  of  Clorer. 

Ashes  of  Clover. 

Ungypsed. 

Gypsed. 

Ungypsed. 

Gypsed. 

Carbonic  acid 

14.2 
3.4 
8.0 
3.2 

23.7 
6.3 

1.0 
19.6 

1.0 
16.8 

2.8 

22.1 
2.9 
6.9 
2.6 

22.4 
5.1 

0.6 
27.8 
0.7 
7.9 
1.0 

21.5 
2.5 
5.4 
2.4 

25.4 
5.6 

0.5 
22.5 

25 
10.0 

2.0 

26.8 
2.2 
5.8 
2.3 

26.7 
7.4 

traces. 
25.3 
0.2 
2.7 
0.6 

Ciilorine 

Phosphoric  acid*  • • . 

Lime 

Magnesia 

Oxide  of  iron,  manganese ; 

Potash  

Soda  

Silica, , 

Loss  and  charcoal 

100.0 

10C.0 

100.0 

100.0 

Carbonic  acid  and  Loss  deducted : 

4.1 
9.7 
3.9 
28.5 
7.6 

15 
23.6 

1.2 
20.2 

3.8 
9.0 
3.4 

99.4 
6.7 

1.0 
35.4 

0.9 
10.4 

3.3 
7.1 
3.1 
33.2 
7.3 

06 
29.4 

2.9 
13.1 

3.0 

8.2 

3.2 

36.7 

10.2 

traces. 
34.7 
0.3 
3.7 

Phnsnhnrir  nriH  ......... 

Snlnhiirir  nriH      ... ... 

Lime 

Oxide  of  iron,  manganese ; 

alumina 

Potash   

Soda 

Bllica 

100.0 

100.0 

100.0 

lOOX 

GYPSUM. 


329 


The  analyses  here  do  not  indicate  the  modes  in  which  the  various 
substances  found  were  combined  in  the  ashes  ;  but  supposing  that 
the  whole  of  the  sulphuric  acid  existed  in  combination  with  lime, 
which  it  most  probably  did,  the  preceding  results  would  meet  us  in 
the  following  shape  :  the  ashes  of  the  clover  grown  upon  soil  with- 
out gypsum  contain  6,0  per  cent,  of  sulphate  of  lime  ;  those  of  clover 
grown  upon  a  soil  with  gypsum,  5.7  per  cent. 

As  it  is  impossible  to  answer  for  so  small  a  difference  as  Sy^Viy 
parts  in  researches  of  this  kind,  we  must  presume  that  the  two  ashes 
contained  the  same  proportions  of  sulphate  of  lime. 

Here,  however,  as  in  all  other  agricultural  questions,  isolated 
analyses  throw  but  little  light  on  the  subject  of  inquiry.  In  order 
that  they  may  enable  us  to  arrive  at  any  definite  conclusion,  two 
new  elements  must  be  taken  into  the  discussion  :  1st.  The  propor- 
tion of  ash  furnished  by  a  given  weight  of  the  forage  gathered  ;  2d. 
The  quantity  of  forage  yielded  by  a  given  surface  before  and  after 
the  use  of  gypsum. 

I  have  taken  from  my  own  observations  the  quantity  of  dry  forage 
yielded  by  the  two  cuttings  of  2d  year's  clover  after  gypsum,  as 
amounting  to  41  cwt.  per  acre.  The  same  surface  in  the  1st  year, 
and  before  the  use  of  gypsum,  would  have  produced  but  9  cwt.  100 
of  dry  clover  gave  : 


Year. 

Clover  ungypsed 1841 

Idem 1842 

Clover  gypsed 1841 

Idem 1842 


Ashes  freed  from 

Ashes. 

carbonic  acid 

Per  acre. 

per  cent. 

12.0 

10.3 

103  lbs 

11.2 

8.8 

89    " 

7.0 

5.4 

248    " 

7.7 

5.6 

257    ♦• 

MINERAL    SUBSTANCES 

tN    THE   CROP 

FROM 

2t\ 

ACRES. 

^^ 

g 

■ 

i 

1 
o 

•c 

1 

02 

i 

3 

.2 
1 

1 

4 

1 

1 

Year  1841. 

lbs. 

lbs. 

lbs. 

lbs. 

lbs. 

lbs. 

lbs. 

lbs. 

lbs. 

lbs. 

Fallow  ung^'psed  .... 

10.1 

24.2 

9.6 

70.8 

18.9 

3.0 

58.7 

3.0 

48.9 

248 

Ditto  gypsed 

22.6 

53.2 

20.2 

174.6 

39.8 

5.9 

210.3 

5.2 

61.8 

594 

Year  1842. 

Fallow  ungypsed  .... 

6.6 

15.4 

6.6 

70.8 

15.6 

1.3 

62.9 

6.1 

27.9 

234 

Fallow  gypsed   

18.4 

50.3 

19.8 

226.1 

62.7 

— 

213.8 

1.7 

22.8 

616 

It  is  therefore  obvious,  that  in  the  course  of  the  three  months 
which  followed  the  application  of  the  gypsum,  the  soil  must  have 
•upplied  the  plant  with  very  considerable  quantities  of  mineral  sub- 
stance ;  the  crops  tak  ^n  from  the  gypsed  soils  contained  in  fact  two 

28* 


S30  GYPSUM. 

or  even  three  times  the  quantity  of  these  substances  which  those 
grown  previously  to  the  gypsing  contained.  Representing,  for  ex- 
ample, by  .nity  the  quantity  of  the  several  bases  and  acids  of  the 
crop  grown  without  gypsum,  we  should  have  the  quantities  of  the 
same  principles  contained  in  the  crops  produced  upon  the  gypsed 
soils  represented  by  the  following  numbers  : 

Phosphoric        Sulphuric  Mag-nesia  and    Potash  and 

Chlorine.  acid.  acid.  Lime.        metallic  oxide.         soda.  Silica. 

1841  2.2  2.2  2.1  2-5  2-1  3.5  1.0 

1842  2.8  3.3  3-1  3.1  3.7  3.2  1.0 

Silica  appears  to  form  the  only  exception  here,  which  would  lead 
as  to  conclude  that  this  earth  was  only  absorbed  by  clover  in  the  first 
period  of  its  growth.  Potash  and  lime  are  the  bases  which  enter  in 
largest  proportion  into  the  mineral  constitution  of  clover  ;  and  there 
is  another  fact  made  evident  which  deserves  particularly  to  fix  at- 
tention :  it  is  that  the  lime  assimilated  subsequently  to  the  gypsing, 
bears  no  kind  of  relation  to  the  quantity  of  sulphuric  acid  fixed  dur- 
ing the  same  space  of  time.  The  excess  of  acid  and  of  lime  obtain- 
ed from  the  ash  of  the  gypsed  clover  over  that  of  the  ungypsed,  is 
for: 

1841,  Sulphuric  acid    4.8        Lime       47.2 

1842,  "  6.0  "  70.6 

Supposing  further,  that  the  sulphuric  acid  assimilated  subsequently 
to  the  gypsing  was  taken  up  in  the  state  of  sulphate  of  lime,  we  find 
that; 

In  1841  the  gj'psed  crop  absorbed  18  lbs.  of  this  salt 
In  1842         "         22  lbs. 

These  quantities  are  so  small  as  to  lead  us  to  suppose  that  the 
utility  of  gypsing  consists  in  furnishing  the  plant  with  the  large  pro- 
portion of  lime  which  it  seems  to  require.  Gypsing  would  then  be 
equivalent  to  the  application  of  lime  ;  and  in  fact,  according  to 
Schwertz,  Paris  plaster  is  replaced  in  Flanders  by  slaked  lime,  by 
the  lye-washed  ashes  of  wood,  and  by  peat-ash,  with  decided  advan- 
tage.* Some  peat-ash  contains  sulphate  of  lime,  others  none  at  all. 
What  is  employed  successfully,  most  likely  presents  sulphuric  acid 
in  the  state  of  an  alkaline  sulphate. 

Wood-ash,  which  is  certainly  the  best  manure  for  artificial  mead- 
ows, may  contain  upon  an  average  one  per  cent,  of  sulphuric  acid, 
and  when  lye- washed,  the  proportion  ought  to  be  much  less  ;  if  per- 
fectly washed,  it  ought  to  be  null ;  at  all  events,  there  is  no  sulphate 
of  lime  present  to  fix  the  ammonia  of  the  rain-water.  Independently 
of  earthy  phosphates,  so  useful  to  all  plants,  lye-washed  ashes  fre- 
quently yield  more  than  80  per  cent,  of  chalk.  We  thus  perceive, 
in  a  general  way,  that  the  manures  which  stimulate  the  vegetation 
of  clover  are  always  calcareous,  the  lime  being  either  in  the  state 
of  sulphate  or  carbonate,  which  exists  abundantly  in  the  crops,  com- 
bined with  organic  acids,  and  freed  consequently  of  nearly  the  whole 
of  the  inorganic  acid  with  which  it  was  originally  associated.  As- 
sui'uog  that  gypsum  acts  like  chalk,  it  may  be  conceived  that  when 

*  Schwertz,  Culture  des  Plantes  fourrag^ret,  p  7t 


I 


GYPSUM.  331 

the  former  is  incorporated  with  the  indispensable  manure,  it  is  de- 
composed, and  carbonate  of  lime,  "».  a  state  of  minute  division,  and 
for  that  reason  easily  absorbed,  is  the  result.  It  is  only  upon  this 
supposition  that  I  can  understand  the  elimiration  of  the  sulphuric 
acid  of  the  gypsum ;  for  if  the  lime  really  entered  the  vegetable  in 
the  state  of  sulphate,  the  ashes  ought  to  be  much  richer  in  that  acid 
than  analysis  shows.  This  same  difficulty  occurs  in  the  hypothesis 
of  Liebig.  If  the  56  lbs.  of  ammonia  derived  from  the  atmosphere 
penetrated  the  plant  in  the  form  of  sulphate,  here  must  enter  at  the 
same  time  130  lbs.  of  sulphuric  acid,  and  which  ought  to  be  recover- 
ed in  the  ashes  of  the  crop  from  one  acre.  Now,  the  ashes  of  41 
cwts.  of  gypsed  clover,  abstracting  the  carbonic  acid,  weigh  2  cwts. 
8  lbs.,  containing  in  the  100,  3^  of  sulphuric  acid.  But  the  amount 
of  ash,  were  the  acid  of  the  ammoniacal  sulphate  fixed  in  the  crop, 
would  rise  to  3  cwt.  1  qr.  20  lbs.,  and  the  ash  would  then  contain 
70  per  cent,  of  sulphuric  acid. 

Before  promulgating  this  last  objection  against  received  theories,  I 
thought  it  right  to  ascertain  whether  the  asLes  contain,  in  the  state 
of  sulphate,  the  whole  of  the  sulphur  pre-existing  in  the  incinerated 
plant.  For  it  was  not  impossible  that  at  the  high  temperature  em- 
ployed, the  silica  might  react  upon  the  sulphates  so  as  to  expel  a 
portion  of  the  sulphuric  acid.  However  improbable  this  expulsion, 
owing  to  the  great  excess  of  potash  always  present  in  clover  ash, 
it  seemed  expedient  to  determine  the  fact. 

After  having  made  out  as  exactly  as  possible  the  quantity  of  ash 
left  by  the  hay,  and  also  the  sulphuric  acid,  I  took  a  certain  weight 
of  the  same  hay,  burned  it  in  a  platina  crucible  along  with  a  mixture 
of  chlorate  and  carbonate  of  potash,  and  then  sought  for  the  sulphu- 
ric acid  in  the  product  of  the  ignition. 

1000  parts  of  the  plant  furnished  directly  3  of  sulphuric  acid,  and 
by  analysis  of  the  ash,  2.8. 

Thus,  the  alkaline  ashes  retain  all  the  sulphur  pre-existing  in  the 
plant  which  produced  them. 

I  have  laid  stress  upon  the  small  proportion  of  sulphuric  acid  in  a 
crop  of  clover,  because  there  yet  remains  for  consideration  a  third 
theory  of  gypsing,  which  I  have  helped  to  propagate,  although 
doubtful  concerning  the  author.  This  is  founded  upon  the  assumption 
that  the  proportion  of  sulphur  is  much  greater  in  the  leguminous 
than  in  the  cereal  tribe.  Now,  as  gypsum  is  generally  adapted  to 
the  manurement  of  leguminous  plants,  the  origin  of  the  sulphur  has 
been  ascribed  to  sulphate  of  lime  incorporated  with  the  soil.  This 
view  appeared  the  more  plausible  to  M.  Dumas  and  myself,  inas- 
much as  in  accordance  with  it  plants  operatod  as  reducing  agents. 
It  is,  besides,  very  probable  that  sulphur,  as  an  immediate  constituen 
principle  of  vegetables,  is  derived  from  sulphates  ;  but  do  leguminous 
plants  really  contain  more  than  the  cereals  ?  This  seems  doubtful 
since  careful  investigation  of  the  azotized  principles  of  plants  has 
shown  gluten,  caseine,  and  legumine  to  be  nearly  identical  in  com- 
position. I  moreover  find  upon  analysis  of  the  ashes,  that  clover 
haricots,  and  beans  do  not  sensibly  contain  more  sulphur  than  ryo- 


•S2  AMMONIACAL    SALTS. 

wheat,  oats,  and  potatoes.  There  appears  to  be  no  doubt,  therefore 
that  the  sulphur  required  by  plants  is  supplied  abundantly  by  the  soil 
enriched  with  ordinary  manure,  as  happens  in  the  culture  of  the 
cereals,  roots,  and  tubers. 

In  a  wcrd,  it  may  be  presumed  that  Paris-plaster  acts  usefully  on 
artificial  meadows  by  introducing  lime  into  the  soil.  This  is  con- 
sistent both  with  the  analysis  of  the  ashes  of  the  crops  produced  and 
of  the  soil ;  for  according  to  the  researches  of  M.  Rigaud  de  I'lsle, 
gypsum  operates  only  upon  soils  which  do  not  contain  a  sufficient 
dose  of  lime  in  the  state  of  carbonate.* 

OF    AMMONIACAL    SALTS. 

The  last  products  of  the  putrefaction  of  azotized  matters  being 
ammoniacal  combinations,  it  necessarily  follows  that  salts  having 
ammonia  for  their  base,  must  act  usefully  in  vegetation.  This  is 
confirmed  by  the  employment  of  guano,  and  by  experiments  in  which 
ammoniacal  compounds  have  been  directly  applied  as  manure.  I 
have  already  pointed  attention  to  the  observations  of  Davy  relative 
to  the  favorable  effect  of  carbonate  of  ammonia  upon  the  develop- 
ment of  plants,  and  shall  now  detail  some  recent  trials  made  by  M. 
Schattenmann  with  the  sulphate  and  muriate  of  the  same  base. 

These  salts  were  introduced  into  the  soil  as  a  solution  marking 
one  degree  of  Beaume's  areometer,  and  in  the  dose  of  102  bushels 
per  acre.  In  1843,  the  effects  produced  upon  wheat  by  muriate 
and  sulphate  of  ammonia  were  most  distinct ;  as  was  also  the  case 
with  natural  meadows,  which  yielded  under  the  influence  of  this 
liquid  manure  82  cwts.  of  hay  per  acre,  precisely  double  the  crop 
afforded  by  the  same  meadow  land  without  the  salts  of  ammonia  ; 
but  another  important  fact,  and  which  M.  Schattenmann  announces 
with  confidence  as  having  been  proved  by  repeated  trials,  is  this ; 
that  solution  of  sulphate  of  ammonia  employed  in  the  same  dose,  and 
at  the  same  degree  of  concentration,  causes  no  appreciable  meliora- 
tion upon  trefoil  and  lucerne.  The  result  of  a  solution  of  sal-am- 
moniac was  equally  negative. 

These  observations  agree  in  certain  points  with  those  formerly 
made  by  Rigaud  de  I'Isle,  and  more  lately  by  M.  Lecoq,  But  they 
are  in  direct  opposition  with  the  experiments  of  several  physiologists 
who  have  studied  the  action  of  ammoniacal  salts  presented  separate- 
ly to  vegetables,  a  circumstance  very  different  from  that  wherein 
ammoniacal  solutions  are  incorporated  with  arable  land.  Thus,  M. 
Bouchardatf  has  stated  that  young  plants  of  mentha  aquatica  and 
sylvestris,  and  of  mimosa  pudica  die  very  soon,  when  made  to  ve- 
getate with  the  roots  plunged  in  very  weak  solutions  of  muriate, 
nitrate,  and  sulphate  of  ammonia.  In  offering,  some  years  back, 
divers  considerations  upon  guano,  I  promulgated  the  opinion  that 
ammoniacal  salts,  in  order  to  serve  as  azotized  manure,  must  alway 
contain  organic  acids  or  carbonic  acid.     Perhaps  the  term  useftk 

•  M*moires  de  la  Soci6t6  d'Agriciilttire,  ann6e  1844. 

t  Bottch»rdat,  Compte*  rendus  de  l'Acad6mle  des  Sciences,  torn.  xvi. 


AMMONIACAL   SALTS.  335 

$alt  may  be  now  restricted  to  the  carbonate  alone.  At  least,  having 
watered  young  plants  of  trefoil,  growr,  in  silicious  sand,  with  solu- 
tion of  oxalate  of  ammonia  at  ir^TT^h*  1  observed  them  die  after  the 
lapse  of  eight  or  ten  days.  Plants  of  the  same  size,  sown  under 
like  conditions,  but  irrigated  with  distilled  water,  continued  to  grow 
and  flowered. 

In  treating  of  gypsing,  I  have  assigned  my  reasons  against  admit- 
ting that  the  azote  fixed  during  the  culture  of  trefoil,  proceeds  from 
the  sulphate  or  muriate  of  ammonia  naturally  absorbed.  I  again 
assert,  that  it  is  materially  impossible  that  ammoniacal  salts  com- 
bined with  inorganic  acids,  other  than  the  carbonic,  can  be  usefui  as 
manure  to  plants,  when  administered  separately  ;  they  can  only  be- 
come advantageous  when  their  composition  has  undergone  modifica- 
tion. 

.Two  cwt.  (220  lbs.)  of  wheat-sheaves,  (straw  and  grain,)  contain 
upon  an  average  2  lbs.  1  oz.  14  dwts.  of  azote,  and  leave  after  igni- 
tion 11  lbs.  3  oz.  16  dwts.  of  ash,  into  which  enter  1  oz.  7  dwts.  of 
sulphuric  acid,  and  14  dwts.  of  chlorine. 

In  the  ammoniacal  salts  : 

100  of  azote  corresponds  to  283  of  sulphuric  acid. 
"  "  257  of  chlorine. 

Let  us  now  consider  sulphate  of  ammonia,  which,  according  to  the 
experiments  of  M.  Schattenmann,  supplied  an  excellent  manure  for 
wheat.  If  the  2  lbs.  1  oz.  14  dwts.  of  azote  contained  in  the  2  cwt. 
of  sheaves  be  derived  from  the  sulphate  absorbed  by  the  cereal,  the 
sulphuric  acid  of  the  sulphate  ought  to  be  recovered  in  its  ashes  ; 
and  according  to  the  above  standard,  these  ashes  ought  to  contain 
6  lbs.  16  dwts.  of  sulphuric  acid.     They  afforded  by  analysis  only 

1  oz.  7  dwts.  

Applying  the  same  reasoning  to  muriate  of  ammonia,  we  find, 

supposing  the  azote  of  the  2  cwt.  of  sheaves  to  emanate  from  this 
salt,  that  the  ashes  should  contain  5  lbs.  6  oz.  2  dwts.  of  chlorine ; 
whereas  they  really  contain  but  14  dwts. 

Without  doubt,  the  nitrogenous  principles  of  the  cereal  cannot  be  re- 
ferred solely  to  the  ammoniacal  salts  in  the  trials  of  M.  Schattenmann; 
the  manure  given  to  the  soil,  and  the  atmosphere  must  have  contribu- 
ted a  share.  The  appreciation  of  the  value  of  ammoniacal  salts  be- 
comes more  precise  when  the  results  obtained  on  meadow  land  are 
estimated.  There  the  produce  was  doubled,  and  of  every  2  cwt.  ol 
hay  gathered,  1  cwt.  may  be  ascribed  to  the  action  of  the  salt. 

Two  cwt.  of  hay,  containing  4  lbs.  16  dwts.  of  azote,  leave  16  lbs, 

2  oz.  of  ash. 

If  the  half  (2  lbs.  8  dwts.)  of  the  azote  of  the  fodder  comes  from 
the  ammoniacal  salts,  the  ashes  will  contain  : 

lb».  oz.         dwu. 

5  8  4       of  sulphuric  acid,  if  the  sulphate  has  been  naed, 

5  2  0  ■'  "     ifth?  mtuiate  has  been        " 

Now,  the  ashes  of  the  hay  yielded  by  analysis  : 

OS.         dwu. 

5  9       of  sulphuric  acid. 

S  4       ofchlorins. 


334  AMMONIACAL    SALTS. 

It  is  then  very  probable  that  if  the  ammoniacal  salts  afford  azote 
to  the  plants,  they  enter  not  as  muriate,  sulphate,  or  phosphate,  be- 
cause there  is  no  reason  to  believe  that  acids  united  with  an  alkali 
are  eliminated  almost  in  totality  during  the  act  of  vegetation.  It 
necessarily  follows,  that  the  ammonia  of  these  salts,  in  order  to  yield 
to  vegetables  its  constituent  azote,  must  reach  their  organs  in  the 
form  of  carbonate,  inasmuch  as  that  is  the  sole  ammoniacal  salt 
which  seems  to  exercise  a  direct  and  favorable  agency. 

However,  if  such  be  the  case,  how  comes  it  to  pass,  that  ammo- 
niacal salts,  as  the  muriate,  phosphate,  and  sulphate,  are  converted 
into  carbonate  when  once  incorporated  in  the  soil  1  Good  arable 
land  almost  always  contains,  it  is  true,  carbonate  of  lime ;  but  there 
is  no  ground  for  admivting  an  acid  interchange  betwixt  the  calca- 
reous and  ammoniacal  salts.  We  know,  on  the  contrary,  that  car- 
bonate of  ammonia  reacts  instantaneously  upon  muriate  and  sulphate 
of  lime,  the  products  of  this  reaction  being  on  the  one  hand  muriate 
and  sulphate  of  ammopia,  on  the  other,  carbonate  of  lime.  The  gyp- 
sum theory  of  Liebig  is  based  upon  the  fact  of  this  double  decompo- 
sition, whereby  the  ammoniacal  carbonate  of  rain-water  is  fixed  in 
the  state  of  sulphate  at  the  cost  of  the  sulphate  of  lime  put  on  the 
ground  as  manure. 

This  reaction  of  sulphate  of  lime  upon  carbonate  of  ammonia  is 
incontestable  as  a  laboratory  experiment ;  but  in  well-tilled  grounds 
containing  just  the  pMper  quantity  of  moisture,  the  reaction  takes 
place  in  the  inverse  sense.  The  carbonate  of  lime  reacts  upon  the 
sulphate  of  ammonia,  and  there  result  carbonate  of  ammonia  and 
sulphate  of  lime. 

This  fact,  however  singular  at  first  sight,  is  explained  upon  prin- 
ciples established  by  Berthollet  in  his  chemical  statics : 

When  two  saline  solutions  are  mixed  together,  and  from  the  mix- 
ture an  insoluble  salt  lesults,  the  insoluble  compound  is  formed  and 
precipitated.  This  is  what  happens  on  pouring  a  solution  of  car- 
oonate  of  ammonia  into  one  of  sulphate  of  lime.  But  if,  instead  of 
Bringing  the  two  salts  together  dissolved,  they  are  mixed  in  a  pul- 
verulent state,  and  just  sufficient  water  is  added  to  promote  the  reac- 
tion without  dissolving  the  products,  a  volatile  compound  forms  and 
is  evolved — namely,  carbonate  of  ammonia. 

The  experimental  proof  is  easy,  and  not  without  interest.  If  chalk 
previously  washed  be  intimately  mixed  with  crystallized  sulphate  of 
ammonia,  no  change  ensues,  provided  the  powders  are  very  dry 
Let  moist  sand  be  introduced  so  as  to  impart  to  the  mixture  the  con- 
sistence of  light  arable  land  of  the  usual  humidity  ;  at  the  very  in- 
stant vapors  of  carbonate  of  ammonia,  cognizable  by  their  action  on 
vegetable  colors  and  their  odor,  are  developed.  When  water  is 
added  in  excess,  the  disengagement  of  ammoniacal  vapor  immedi- 
ately ceases.  The  carbonate  of  ammonia  not  yet  volatilized,  dis- 
solves and  acts  upon  tie  ready  formed  gypsum  so  as  to  constitute 
sulphate  of  ammonia  and  carbonate  of  lime.  The  ordinary  reaction 
is  restored.  Finally,  this  watery  mixture  being  exposed  to  the  air 
furnishes  anew  ammoniacal  vapors  in  proportion  as  the  watei  vapor 


AMMONIACAL    SALTS.  SS"- 

1268,  and  the  volatile  salt  is  progressively  evolved  until  the  ma?s  is 
quite  dry.  In  maintaining  a  similar  mixture  in  a  fit  and  constant 
state  of  moisture  we  may  in  two  or  three  days,  under  the  influence 
of  a  temperature  of  from  68"  to  80°  F.,  dissipate  the  greater  portion 
of  the  ammonia  of  the  sulphate,  and  obtain  a  quantity  of  sulphate  of 
lime  indicating  the  progress  of  the  reaction. 

It  is  almost  needless  to  remark  that  sulphate  of  lime,  placed  in  a 
condition  of  moisture  analogous  to  that  of  the  chalk,  undergoes  no 
alteration  from  the  carbonate  of  ammonia.  Thus,  in  the  ordinary 
circumstances  of  humidity  of  cultivated  land,  it  is  at  least  doubtful 
whether  the  plaster  difl^used  through  it  definitively  retains  the  am- 
monia of  the  rain-water  in  the  state  of  sulphate. 

To  estimate  the  sulphate  of  lime  produced  by  the  reaction  between 
the  sulphate  of  ammonia  and  carbonate  of  lime,  the  mixture  after 
having  been  entirely  dried  in  the  air  is  to  be  treated  with  cold  water. 
The  lime  of  the  sulphate  dissolved  is  next  thrown  down  by  oxalate 
of  ammonia,  and  computed  in  the  state  of  carbonate. 

In  order  to  ascertain  the  presence  of  sulphate  of  ammonia  the 
mixture  is  to  be  digested  in  dilute  alcohol,  which  dissolves  this  salt 
without  taking  up  sulphate  of  lime. 

Muriate,  phosphate,  and  oxalate  of  ammonia  comport  themselves 
as  the  sulphate.  Carbonate  of  lime  decomposes  them  under  the 
same  circumstances,  giving  rise  to  equivalent  products.* 

The  preceding  facts  may  perhaps  tend  to  reconcile  the  contra- 
dictory results  obtained  in  the  application  of  ammoniacal  salts  as 
manure.  When  muriate,  phosphate,  or  sulphate  of  ammonia  is  pre- 
sented to  plants,  these  salts  produce  no  useful  effect ;  they  are  ab- 

*  1.  15.4  grains  of  crystallized  sulphate  of  ammonia  incorporated  with  five  or  six 
times  its  weight  of  chalk,  gave  after  two  days'  exposure  of  the  moist  mixture  in  the 
open  air,  12.3  grs.  of  sulphate  of  lime.  In  another  experiment  16.0  grs.  of  sulphate  of 
ammonia  were  obtained  from  13.1  grs.  of  calcareous  sulphate.  Now  according  to  the 
proportions  of  ammoniacal  salt  there  ought  to  have  been  obtained  13  grs.  and  14  grs. 
of  salpl.ate  of  lime.  Thus  about  9-lOths  of  the  arnmonia  contained  in  the  sulphate  sub- 
mitted to  experiment  had  been  converted  into  carbonate. 

2.  16.9  grs.  of  sulphate  of  ammonia  were  mixed  with  123.2  grs.  of  chalk,  and  fronc 
924  to  1071  grs.  of  silicious  sand.    The  mixture  was  kept  moist  and  exposed  to  the  ail 
during  four  days,  the  temperature  ranging  from  68°  to  80°  F.    The  substance,  afte* 
being  dried  by  the  action  of  the  air,  was  set  to  digest  in  weak  alcohol ;  the  alcoholi 
liquor  yielded  only  an  insignificant  trace  of  sulphate  of  ammonia.    There  was  aboi 
18.5  grs.  of  sulphate  of  lime. 

3.  A  very  simple  means  of  determining  the  reaction  in  question  consists  in  plunginw 
a  fragment  of  chalk  into  a  solution  of  siflphate  of  ammonia  ;  the  fragment  so  imbued 
on  being  exposed  to  the  air  emits  during  several  days  fumes  of  carbonate  of  ammonia. 
Several  bits  of  chalk  moistened  in  the  solution,  and  exposed  by  the  aid  of  an  aspiraloi 
to  a  continuous  current  of  air,  afterwards  washed  in  muriatic  acid,  disengaged  enougk 
of  ammoniacal  vapor  to  form  in. the  acid  nearly  15  grs.  of  sal-ammoniac. 

4.  With  a  slightly  moistened  silicious  sand  were  incorporated  30.8  grs.  of  gypsum; 
the  mixture  then  watered  with  a  solution  containing  30.8  grs.  of  carbonate  of  ammo 
nia,  was  allowed  to  remain  in  the  air  during  eight  days,  having  always  the  consistence 
and  humidity  of  arable  land.  At  the  end  of  this  time  it  was  dried,  then  treated  witfc 
weak  alcohol;  the  alcoholic  fluid  evaporated  left  no  sulphate  of  ammonia. 

5.  Phosphate  of  ammonia,  mixed  with  chalk,  and  kept  in  a  moist  state  for  somf 
days,  comported  iJself  exactly  as  the  sulphate  in  the  same  circumstances ;  9-lOths  ot 
the  ammoniacal  phosphate  were  converted  into  phosphate  of  lime. 

6.  The  reaction  of  oxalate  of  ammonia  upon  chalk  is  visible  even  when  the  mixturi 
is  well  watered  ;  this  is  explained  indeed  by  the  powerful  affinity  of  oxalic  acid  fo» 
lime.  The  totality  of  the  alkaline  oxalate  is  promptly  changed  into  oxalate  of  linH 
Ai»-^  carbonate  of  ammonia. 


336  WATER. 

sorbed  in  limited  quantity,  like  the  majority  of  soluble  substances 
But  if  instead  of  administering  them  separately  dissolved  in  water, 
as  was  done  in  the  physiological  experiments,  they  are  incorporated 
with  a  loose  and  humid  soil,  these  salts  react  upon  the  calcareous 
matter  almost  always  existing  in  the  ground,  and  are  transformed 
into  carbonate  of  ammonia,  which  exerts  undeniably  a  favorable  in- 
fluence upon  vegetation.  From  these  facts  it  may  be  presumed 
that  the  introduction  of  lime  and  marl  is  not  merely  to  supply  the 
defective  calcareous  element,  but  likewise  a  principle,  carbonate  of 
lime,  which  produces  a  particular  action  upon  the  manure,  changing, 
through  double  decomposition,  the  unassimilable  ammoniacal  salts 
there  present  into  a  carbonate  capable  of  being  assimilated,  which 
transmits  to  the  plant  the  azote  of  the  organic  matter  of  the  dung 
and  the  carbon  contained  in  the  calcareous  rocks. 

These  reactions  which  go  on  between  soluble  salts  and  one  that 
is  insoluble  under  the  peculiar  conditions  united  in  arable  land,  show 
that  we  must  not  always  conclude  as  to  what  passes  in  the  ground 
from  phenomena  observed  in  the  laboratory  of  the  chemist ;  and  it 
is  probable  that  by  extending  the  study,  of  these  singular  reactions 
to  alkaline  salts  generally,  we  shall  better  understand  the  mode  of 
action  and  utility  of  saline  substances  in  agriculture.  Thus,  for 
example,  the  operation  of  common  salt  as  a  fertilizer  is  still  very 
obscure.  Many  skilful  husbandmen  question  its  efficacy  ;  neverthe- 
less, when  moderately  employed  it  seems  to  do  good.  In  plants 
growing  on  the  sea-coast  soda  is  found  in  a  great  measure  com- 
bined with  organic  acids,  and  the  chlorine  deduced  by  analysis  from 
their  ashes  is  nowise  proportional  to  the  alkali  they  contain.  The 
whole  sodium  does  not  enter  the  vegetable  as  a  chloride,  but  very 
likely  as  carbonate  of  soda,  and  that  in  virtue  of  a  reaction  analogous 
to  the  one  which  calcareous  matter  has  upon  ammoniacal  salts. 

It  is  quite  certain  that  chloride  of  sodium  in  solution  is  not  affect- 
ed by  carbonate  of  lime ;  but  then  it  was  proved  by  Clouet  that  if 
into  sand  moistened  with  this  same  solution  powdered  chalk  be  put, 
and  the  mixture  left  in  contact  with  air,  an  efflorescence  of  sesqui- 
carbonate  of  soda  ere  long  makes  its  appearance.  Thus  by  the 
conjoint  effect  of  capillarity  and  the  carbonic  acid  of  the  atmosphere, 
common  salt  in  the  conditions  above  mentioned  undergoes  by  contact 
with  chalk  a  partial  decomposition,  of  which  the  result  is  carbonate 
of  soda,  a  salt,  like  carbonate  of  potash,  most  favorable  to  the  growth 
of  plants.  Accordingly,  in  furnishing  sea-salt  to  a  soil  sufficiently 
calcareous,  we  really  enrich  it  with  carbonate  of  soda.  We  more- 
over perceive  that  the  same  salt  diffused  through  land  devoid  of 
carbonate  of  lime  may  not  produce  any  fertilizing  effect. 

OF    WATER. 

Water  is  not  only  indispensable  to  the  life  of  plants,  but  likewi** 
promotes  vegetation  after  the  manner  of  a  manure,  on  account  of 
the  saline  or  organic  substances  it  generally  holds  in  solution.  Rain 
is  the  source  of  the  soft  waters  which  flow  in  rivers,  spring  from 


WATER.  337 

the  soil,  or  constitute  lakes.  Rain-water  although  nearly  pure  is 
not  absolutely  exempt  from  extraneous  matters.  The  air,  especial- 
ly after  continued  drought,  always  holds  dust  in  suspension ;  this 
yields  to  the  rain  by  which  it  is  precipitated,  whatever  soluble  mat- 
ter it  may  contain. 

It  is  further  ascertained  by  the  experiments  of  Cavendish  and 
Seguin,  that  whenever  the  electric  spark  traverses  a  humid  mixture 
of  oxygen  and  azote,  nitric  acid  and  nitrate  of  ammonia  are  produced. 
Now  this  frequently  happens;  and  according  to  Professoi  Liebig 
storm-rain  always  contains  nitric  acid  associated  with  lime  or  ammo- 
nia. Common  rain  seldom  contains  nitrates,  merely  faint  traces  of 
common  salt.* 

In  river  and  spring- water  there  necessarily  exists  a  larger  amount 
of  dissolved  substances  derived  from  the  strata  they  pass  through, 
varying  in  nature  according  to  the  geological  structure  of  the  locali- 
ty. From  old  crystalline  rocks,  like  granite,  water  issues  sometimes 
so  little  impregnated  with  salts,  as  to  be  almost  identical  with  dis- 
tilled water  ;  that,  on  the  contrary,  which  rises  from  a  calcareous  or 
gypseous  bed  is  always  contaminated  with  salts  of  lime.  Notwith- 
standing the  minute  quantity  of  saline  or  earthy  ingredients  in  spring 
and  river-waters,  they  are  drinkable,  and  considered  good  when 
they  are  limpid,  without  odor,  capable  of  dissolving  soap,  and  fitted 
for  vegetable  cookery.  These  two  last  characters  are  essential, 
inasmuch  as  proving  that  the  waters  contain  only  infinitesimal  quan- 
tities of  soluble  salts  of  lime. 

The  action  of  tests  readily  indicates  the  nature  of  the  dissolved 
salts. 

Water  contains :  sulphates  or  carbonates,  if  nitrate  of  barytes 
causes  a  precipitate  ;  a  sulphate,  when  the  precipitate  is  not  redis- 
solved  by  the  addition  of  nitric  acid  ; 

Chlorides,  if  it  give  with  nitrate  of  silver  a  curdy  precipitate,  in- 
soluble upon  addition  of  nitric  acid; 

Lime,  when  rendered  turbid  by  oxalate  of  ammonia ; 

Magnesia,  if  when  mixed  with  pure  ammonia,  and  preserved  in  a 
closely  stopped  vial,  a  white  flocculent  deposite  ensues.  This  test, 
however,  is  only  applicable  to  water  that  has  been  boiled  sufficiently 
long  to  expel  all  the  carbonic  acid  in  solution,  and  which  would  tend 
to  hold  any  carbonate  of  lime  dissolved.  Carbonate  of  lime  is  sepa- 
rated from  water  by  ammonia,  after  some  hours,  in  the  form  of  gran- 
ular crystals,  which  adhere  to  the  sides  of  the  vessel. 

In  order  to  render  the  operation  of  tests  more  sensible,  the  bulk 
of  the  water  may  be  reduced  to  a  half  or  a  fourth  by  evaporation. 

Besides  fixed  salts,  river- water  always  contains  those  of  ammo- 
nia, particularly  the  carbonate  ;  this  fact  was  first  ascertained,  re- 
lative to  the  Seine  water,  by  M.  Chevreul.f  Subsequently,  Pro- 
fessor Liebig  has  discovered  the  same  ammoniacal  salt  in  rain-wa- 
ter ;  and  M.  Hunefeld  has  proved,  that  spring-water  likewise  con- 


*  Annales  de  Chimie,  t.  xxxv.  2e  s6rie. 

t  Chevreul,  Annales  de  Chimie,  t.  Ixxxii.  p.  5(1 


.  888  WATER. 

tains  it.*  Lastly,  M.  Hermann  has  even  determined  quanlitatirely, 
carbonate  of  ammonia  in  the  ferruginous  waters  of  a  turf-pit.  The 
water  of  the  Nile  is  not  exempt  from  it,  judging  at  least  from  the 
analysis  of  its  mud.  According  to  Regnault,  100  parts  of  this  mud 
dried  in  the  air  contain  :t 

Chloride  of  sodium,  sulphate  of  soda,  and 

carbonate  of  ammonia J 

Organic  matter 9 

Water 10 

Oxide  of  iron 6 

Silica 4 

Alumina 48  " 

Carbonate  of  lime 18 

Carbonate  of  magnesia 4 

100 

The  beautiful  synthetic  experiments  of  M.  Dumas  demonstrate 
that  water  is  formed  of: 

Oxygen 88.89 

Hydrogen 11.11 

When  pure,  it  boils  at  a  temperature  of  212°  F.  under  a  barome- 
tric pressure  of  30  (29.921)  inches.     It  congeals  at  32°  F. 

All  natural  bodies  dilate,  augment  in  volume,  by  the  action  of 
heat,  and  contract  under  diminution  of  temperature.  Water  is 
amenable  to  this  law  between  rather  wide  limits  ;  it  deviates,  how- 
ever, and  presents  an  anomaly  as  it  approaches  congelation.  As 
with  all  liquids,  the  density  of  water  gradually  increases  in  propor- 
tion as  it  cools,  until  its  temperature  is  39°.38  F.  Setting  out  from 
this  point  the  density  diminishes,  the  liquid  dilates  more  and  more, 
CO  that  at  32°  it  occupies  nearly  the  same  volume  that  it  did  at  49°. 
From  this  remarkable  property,  it  results  that  during  the  most  in- 
tense cold  the  stagnant  water  which  covers  the  meadows  rarely  at- 
tains a  lower  temperature  than  39°,  whereby  the  organs  of  plants 
suffer  no  damage. 

Let  us  suppose,  in  fact,  that  at  the  beginning  of  winter  a  sheet  of 
stagnant  water  has  a  temperature  of  about  54° ;  in  proportion  as  the 
liquid  at  the  surface  cools,  it  becomes  denser,  descends,  and  is  im- 
mediately replaced  by  inferior  layers,  which  rise  in  the  ratio  of  their 
less  density ;  but  these  new  superior  layers,  subjected  to  the  same 
refrigerating  cause,  contract  and  descend  alternately.  There  is 
then  established  in  the  fluid  molecules,  movements  of  ascension  and 
descent,  of  which  the  result  is  the  cooling  of  the  entire  mass.  Let 
us  now  admit  that  in  virtue  of  this  continued  mingling  of  the  cooled 
superior  layers  with  those  below,  the  temperature  of  the  sheet  of 
water  is  lowered  to  39°.  38  ;  at  this  degree  of  the  thermometer,  the 
water  acquires  its  maximum  density  ;  in  parting  with  its  heat  it  not 
only  contracts  no  more,  but  becomes  lighter.  If  then  a  body  of 
stagnant  water  at  a  temperature  of  39°  is  exposed  to  the  chilling 
action  of  the  atmosphere,  the  superior  layer,  far  colder  than  the  in- 
ferior, will  no  longer  descend,  since  it  will  become  lighter  as  its 

*  Lieblg,  Traits  de  Chimie,  Introduction,  p.  cii. 
t  Dwcription  d«  TEgypte,  t.  li.  p.  405. 


WATBR,  ;>39 

temperature  diminishes.  Thus  it  is  that  the  water  of  a  pond  or  lake 
freezes  at  the  surface,  while  it  preserves  beneath  a  tempciature 
some  degrees  above  32°.  In  a  situation  where  the  temperature  of 
the  air  was  29",  Davy  found  the  thermometer  indicate  43"  in  he 
herbage  of  an  inundated  meadow  completely  covered  with  ice.* 

Water  is  always  impregnated  with  atmospheric  air,  and  a  minjte 
quantity  of  carbonic  acid.  Deprived  of  air,  it  is  not  agreeable  to 
drink ;  it  is  even  said,  when  long  continued,  to  prove  unwholesome 
if  the  dissolved  gases  are  expelled  by  ebullition.  River-water  usual- 
ly contains  3'^  th  in  volume  of  air,  and  tJ'o  th  carbonic  acid.  In  spring- 
water,  the  amount  of  the  latter  is  sometimes  far  more  considerable. 

The  quantity  and  nature  of  saline  ingredients  in  drinkable  water 
vary  much  :  in  an  agricultural  point  of  view,  the  study  of  the  con- 
tained salts  would  certainly  be  useful.  The  waters  which  serve  as 
drink  to  the  cattle  of  a  farm,  introduce  into  the  dung-heap  all  the 
matters  which  are  dissolved  or  held  in  suspension.  At  Bechelbronn, 
for  example,  I  find  that  more  than  2  cwts.  of  alkaline  salts  get  into 
the  dung  in  this  way  every  year.  When  a  farmer  has  the  choice  of 
several  waters  for  giving  his  cattle  or  irrigating  his  meadows,  he 
will  do  well  to  select  that  which  is  richest  in  alkaline  salts,  and  still 
good  to  drink.  In  the  steppes  of  America,  it  is  astonishing  with 
what  discernment  the  cattle  choose  waters  for  allaying  their  thirst, 
containing  minute  quantities  of  sulphate  of  soda  or  common  salt. 

I  close  these  considerations  with  a  tabular  view  of  the  most  recent 
analyses.  The  quantities  of  salts  put  down  have  been  deduced  from 
100,000  parts  of  water  for  drinking. 

*  Davy.  Agricultural  Chemistry,  p.  3S9 


540 


V/ATER. 


Of  the  Seine  above  Paris  . 

Marne 

Onrcq  at  St.  Denis  .     . 

Yonne  at  Avalion    .     . 

Benvronne       .     .     .     . 

Therouenne     .     .     .     . 

Gergogne 

Bievre  near  Paris     .     . 

Arcueil 

Spring  of  Roye  (Lyons)  . 
Fountain  Spring  (Lyons) . 
Rhone  at  Lyons  (July) 
Ditto  ditto  (February)      . 
Spring  of  the  garden  of 

plants  at  Lyons   .     .     . 
Of  Lake  Geneva     .     .     . 
Of  the  Arve  (in  August)  . 
Ditto  in  February    .     .     . 
Loire  near  Orleans  .     .     . 
Loiret 

1 

H 

•< 

H 

59 

i_i                           to        (->  h-  to  lO  k-  I-- l-»  JO  to        t->y-i)-i 
^  y-t  OD  Ox -^  ■<l       t;iowcoasCopop:>cn4i.;-TpH-' 

Carbonate  of 
lime. 

Carbonate  of 
magnesia. 

..pop-            •      §    B    O ^PPP 

Silica. 

w-    ojccjoc^      tspK-"  H- as  S  H- too  g  o^  woo 
bo*    cnioosio      oc5^*^«o^-'C^bc»5ctWH-a3 

00 

Sulphate  of 
lime. 

•    •    b  «3  F-  •        ^  g b  to  en 

Sulphate  of 
magnesia. 

Sulphate  of 
Soda. 

ho*-''    '    '    bo      ^aw-biocnboibi'-b 

Chloride  of 
calcium. 

cn-jix)a5               g'                          'o^ioo 

Chloride  of 
magnesium. 

traces 
idem 

0.9 
1.2 
1.9 
1.2 
0.2 
traces 

12.6 

traces 
2.5 

Chloride  of 
sodium  (marine 

salt.) 

traces 

traces 

of  lime 
7.6 

Nitrates. 

traces 
idem 
idem 
idem 

•  • 

•  • 

traces 
idem 
idem 
idem 
strong 
traces 
0.6 
0.3 
0.4 

Organic  matter. 

lO        to  I-"  1—  CO        I—  ^  to  to  rfi.  C^  to  W  trt        rf>.  —  i-i 
00  OS  *^  to  Cn  O        OD  O  05  05  CS  O  — '  ^  4^  -^  ^  OC  00 

'►f^  bo  00  00  io  bo      i^  bs  05  4^  ^  bo  b  bo  c/i  ^  bo  b  to 

Total  weight  of 
matter. 

Bouchardat 

Ditto 

Ditto 

Ditto 

Colin 

Ditto 

Ditto 

Ditto 

Ditto 

Bot.J8ingauIt 

Dupasquier 

Boussingault 

Dupasquier 

Ditto 

Tingry 

Ditto 

Ditto 

Guindant 

Ditto 

ROTATION.  341 

The  water  of  the  Artesian  well  at  Grenelle,  near  Paris,  according 
to  the  analysis  of  M.  Payen,  contains,  in  100,000  parts  : 

Carbonate  of  lime 6.80 

Carbonate  of  magnesia 1.42 

Bicarbonate  of  potash ...2.96 

Sulphate  of  potash 1.20 

Chloride  of  potassium 1.09 

Silica 0.57 

Yellow  matter,  not  defined 0.02 

Organic  azotized  matter  .. 0.24 

14.30 


CHAPTER  VII. 
OF  THE  ROTATION  OF  CROPS; 

^  1.    OF  THE  ORGANIC  MATTER  OF  MANURE  AND  OF  CROPS. 

It  is  known  that  the  atmosphere  and  the  organic  matters  diffused 
through  the  earth  concur  simultaneously  to  maintain  the  life  of 
plants ;  but  how  far  each  contributes  is  undetermined.  We  shall  now 
study  the  theory  of  the  exhaustion  of  the  soil  by  culture,  and  the 
rotation  of  crops. 

When  a  succession  of  crops  is  grown  upon  fertile  land  without 
renewal  of  manure,  the  produce  gradually  diminishes  ;  and  after  a 
certain  period,  if  it  be  grain,  the  quantity  which  at  the  outset  was 
eight  or  nine  limes  the  amount  of  the  seed,  will  be  reduced  to  three 
times  or  even  to  twice  the  seed.  Thus  crops  impair  the  fertility  of 
the  soil,  and  eventually  exhaust  it. 

It  has  been  long  admitted  that  different  species  of  plants  manifest 
great  diversity  in  their  powers  of  exhaustion.  Certain  kinds,  indeed, 
as  trefoil  and  lucerne,  far  from  exhausting  it,  communicate  new 
vigor.  As  a  general  rule,  however,  every  plant  may  be  said  to 
impoverish  the  soil  in  which  it  grows.  This  impoverishment  is  al- 
ways manifest  when  the  plant  after  maturity  is  completely  removed, 
but  is  less  sensible  when  much  rubbish  is  left.  Thus,  for  example, 
clover,  after  yielding  two  crops,  which  are  generally  cut  as  fodder, 
might  still  yield  a  third  ;  this  last,  however,  is  generally  ploughed 
into  the  ground  as  manure,  being  buried  along  with  a  considerable 
quantity  of  roots.  This  plan  of  meliorating  the  soil  by  the  cultiva- 
tion of  trefoil  is  what  is  called  manuring  by  smothering ;  a  method 
practised  from  a  remote  period  in  the  south  of  Europe,  and  which 
offers  decided  advantages  in  those  districts  where  there  is  abun- 
dance of  pasture  land.  Hence,  in  smothering  trefoil,  the  soil  is 
amended  at  the  expense  of  the  nutritive  matter  it  contains. 

Thaer,  who  endeavored  to  make  theory  and  practice  mutually 
agree,  laid  it  down  as  a  rule,  that  the  exhaustion  occasioned  b_> 

29* 


842  ROTATION. 

cropping  is  proportioned  to  the  amount  of  nutriment  in  the  crops 
estimating  the  nutritive  value  according  to  Einhof  s  determination 
But  the  above  deduction  is  founded  upon  error. 

In  fact,  to  adopt  the  above  principle  is  tacitly  admitting  that  the 
whole  organic  matter  of  plants  originally  comes  from  the  soil.  This, 
no  doubt,  contributes  in  a  certain  proportion  to  the  development  of 
plants,  but  so  also  do  air  and  water.  On  the  other  hand,  physiolo- 
gists, in  opposition  to  the  ideas  of  the  school  of  Thaer,  have  perhaps 
exaggerated  the  material  withdrawn  from  the  air.  Thus,  M.  de 
Saussure  reckons  that  a  sun-flower  derives  from  the  ground  during 
its  growth  not  more  than  ^oth  of  its  weight,  supposing  the  plant  dry. 
The  reasoning  upon  which  he  formed  his  conclusion  is  based,  on  the 
one  hand,  upon  a  knowledge  of  the  extractive  matter  of  garden- 
mould  ;  on  the  other,  upon  the  quantity  of  water  a  plant  like  sun- 
flower may  absorb  in  a  given  time,  to  return  it  again  to  the  air  by 
transpiration.* 

Little  objection  could  be  urged  against  the  above  conclusion,  did 
not  the  experiments  of  M.  Gazzeri  tend  to  prove  that  roots  virtually 
exercise,  by  their  contact  with  solid  organic  matter,  an  incontesta- 
ble absorbent  action  in  imparting  solubility.f  I  might  refer  to  an 
observation  of  M.  de  Saussure,  in  which  he  states  that  plants  grown 
in  garden-mould  deprived  of  its  soluble  components  by  repeated 
washing,  reached,  nevertheless,  perfect  maturity,  although  the  pro- 
duce in  seed  was  less  abundant  than  it  might  have  been. J  It  is 
most  probable  that  both  parties  have  promulgated  extreme  opinions. 
Plants  possibly  draw  from  the  atmosphere  more  than  agriculturists 
commonly  suppose,  and  the  soil  furnishes,  independently  of  saline 
and  earthy  substances,  a  proportion  of  organic  matter  larger  than 
certain  physiologists  admit.  There  is  every  reason  to  believe,  from 
what  I  could  learn  respecting  guano  during  my  sojourn  on  the  coast 
of  Peru,  that  the  greater  part  of  the  azotized  principles  of  plants 
originates  in  the  ammoniacal  salts  which  exist  or  are  formed  in  ma- 
nure.^ 

In  discussing  the  advantage  of  one  course  of  crops  over  another, 
the  question  always  hinges  upon  that  of  exhaustion.  Wherever  an 
unlimited  supply  of  dung  and  of  handiwork  can  be  procured,  there 
is  no  absolute  necessity  for  following  any  regular  system  of  rotation. 
Under  such  favorable  circumstances,  it  is  expedient  to  ascertain 
what  kind  of  cultivation  is,  commercially  speaking,  best  suited  to 
the  climate  and  the  soil.  There  is  little  to  fear  that  by  a  continued 
succession  of  similar  crops,  the  fields  will  get  infested  with  noxious 
weeds,  because  this  inconvenience  may  be  obviated  by  labor.  Nor 
is  impoverishment  of  the  soil  to  be  dreaded,  since  that  can  be  re- 
medied by  the  purchase  of  manure.  The  whole  craft  of  agricuhure 
is  reducible  to  comparison  of  the  probable  value  of  the  crop  with 
the  cost  of  manure,  labor,  &c.     Farming  of  this  sort  excludes  the 

*  Saussure,  Recherches  Chimiques  sur  la  V6g6tation,  p.  2681 
t  Annales  de  rAj^TicuUnrc  Franfaise,  No.  iii.  p.  57 
i  Saussure,  Recherches  Chimiques,  p.  171. 
^  Annales  de  Chimie,  t.  Ixv.  ann^  1837. 


ROTATION.  843 

keep  and  propagation  of  cattle,  and  may  be  strictly  regarded  morfe 
as  gardening  than  as  agriculture. 

But  where  manure  cannot  be  had  from  without,  things  must  be 
reduced  to  a  system ;  and  the  amount  of  produce  which  it  is  possi- 
ble to  export  each  year  is  fixed  within  bounds,  which  cannot  be  ex- 
ceeded with  impunity. 

When  by  judicious  cultivation  land  is  rendered  fertile,  it  is  ne- 
cessary, towards  securing  its  fertility,  to  supply  after  every  succession 
of  crops  equal  quantities  of  manure.  In  considering  this  in  a  purely 
chemical  point  of  view,  it  may  be  said  that  the  produce  which  can 
be  taken  away  without  damaging  the  fertility  of  the  land,  is  the  or- 
ganic matter  contained  in  the  crops,  abstraction  made  of  that  present 
in  the  manure.  Indeed,  this  latter  substance  must  in  some  form  or 
other  return  to  the  soil  to  fecundate  it  anew.  It  is  capital  placed  in 
the  ground,  the  interest  of  which  is  represented  by  the  commercial 
value  of  the  produce  of  all  the  other  agricultural  operations. 

Where  lands  are  extensive,  population  scattered,  and  means  of 
communication  difficult,  there  is  less  necessity  for  being  tied  down  to 
systematic  cultivation.  There  is  always  enough  for  a  scanty  popu- 
lation. A  field  yields  grain,  and  after  the  harvest  is  converted  for  a 
series  of  years  into  meadow-land  ;  such  is  the  pastoral  system  in  all 
its  simplicity.  To  this  primitive  state  of  husbandry  may  be  referred 
those  plantations  on  cleared  land  in  countries  covered  with  forests. 
When  the  trees  are  felled  and  burned  upon  the  spot,  the  soil  yields 
for  long  and  without  manure,  crops  of  maize  and  of  wheat  of  sur- 
prising quality,  at  the  cost  of  the  fecundity  acquired  during  ages  of 
repose. 

But  when  from  increased  population  the  land  becomes  more  valu- 
able, a  larger  amount  of  produce  is  demanded.  Imperfect  culture 
would  prove  inadequate.  Accordingly  a  triennial  rotation  of  crops 
was  very  anciently  adopted  in  the  north  of  Europe,  consisting  as  is 
well  known  of  fallow  land  frequently  ploughed  during  summer,  fol- 
lowed by  two  years  of  grain.  The  fallow  land  received  a  certain 
quantity  of  manure  to  repair  the  exhaustion  occasioned  by  the  two 
crops  of  grain  ;  hence  when  this  mode  of  rotation  is  adopted  there 
should  be  always  sufficient  meadow-land  to  supply  manure. 

Leaving  waste  one  third  of  the  surface  has  always  been  held  a 
grave  objection  against  triennial  rotation.  Hence  various  attempts 
have  been  made  to  get  rid  of  the  summer  fallow.  Some  encourage- 
ment was  given  to  these  attempts  from  what  occurs  in  horticulture, 
where  the  ground  is  rendered  continually  productive.*  In  certain 
countries,  moreover,  tillage  is  only  interrupted  by  severe  weather. 

On  the  other  hand,  it  has  been  long  remarked  that  it  is  not  always 
beneficial  to  grow  grain  during  several  consecutive  years  in  the 
same  ground,  even  when  it  is  fertile  and  manure  is  abundant,  owing 
to  the  almost  insurmountable  difficulty  of  destroying  weeds.  The 
fallow  was  justly  considered  the  most  efficient  and  economic  means 
of  getting  rid  of  these.    For  this  ^pmpose  fallow-crops^  as  they  were 

•  Thaer,  Agricaltnre  ndsonn^e. 


844  ROTATrON. 

called,  were  intrDcIuced.     Peas,  beans.  vetcheS;  were  at  first  tht 
only  plants  used  as  fallow-crops. 

However,  it  was  soon  perceived  that  the  fallow-crops  occasioned 
a  very  sensible  diminution  in  the  produce  of  corn  ;  to  counteract 
this  inconvenience  recourse  was  had  to  a  surcharge  of  manure  ;  but 
as  this  cannot  always  be  obtained,  it  was  necessary  either  to  reduce 
the  cultivated  surface  or  to  appropriate  a  certain  amount  of  meadow. 
Still  the  fallow-crops  had  this  advantage,  that  they  enabled  the  farm- 
er to  derive  from  land  a  greater  amount  of  produce  in  a  given  time 
without  prejudice  to  the  raising  of  corn.  Hence  the  plan  of  turn 
ing  the  fallow  to  account  was  soon  generally  adopted. 

The  introduction  of  clover  so  modified  the  system  of  fallow-crops 
as  at  one  time  to  induce  the  belief  that  the  point  of  perfection  had 
been  attained  in  agriculture.*  This  was  when  it  was  ascertained 
that  trefoil,  which  had  hitherto  been  only  cultivated  in  small  enclo- 
sures, might  be  sown  in  spring  upon  corn  land,  and  occupy  next 
year  the  place  of  the  fallow  in  the  triennial  rotation.  Trefoil,  so  far 
from  exhausting  the  soil,  was  found  to  give  it  new  fertility,  and  the 
succeeding  corn  crop  yielded  a  plentiful  harvest. 

It  may  be  easily  conceived  what  advantages  were  expected  in 
substituting  for  the  unproductive  fallow  the  cultivation  of  a  plant 
which  did  not  impoverish  the  land,  and  furnished  a  quantity  of  ex- 
cellent fodder  that  served  as  food  for  an  additional  number  of  cattle. 
It  was  even  alleged  that  this  plant  cleared  the  fields  of  weeds. 

A  few  years'  experience  sufficed  to  show  that  trefoil  did  not  pos- 
sess all  the  advantages  attributed  to  it.  On  renewing  the  clover 
every  third  year  on  the  same  piece  of  ground  it  sometimes  failed. 
Schubarth,  the  most  zealous  and  enlightened  advocate  for  its  use, 
limited  the  renewal  of  the  artificial  meadow  at  first  to  the  sixth,  and 
eventually  to  the  ninth  year ;  and  finding  that  it  did  not  completely 
destroy  the  weeds  in  corn,  he  had  recourse  to  hoed-crops  for  that 
purpose. 

The  introduction  of  trefoil  has  gradually  led  to  the  system  of  al- 
ternate rotation  of  crops  generally  adopted  at  present ;  and  more- 
over, contrary  to  the  anticipations  of  Schubarth,  it  may  be  renewed 
every  four  or  five  years  on  the  same  parcel  of  land. 

The  impossibility  of  substituting  trefoil  for  the  fallow  of  the  trien- 
nial rotation  was  offered  as  a  fresh  proof  of  the  principle  maintained 
from  time  immemorial  by  agriculturists,  namely,  that  diflferent  species 
of  plants  should  be  cultivated  in  succession  on  the  same  land,  and 
that  the  same  species  should  not  recur  except  at  considerable  in- 
tervals ;  the  earth  yielding  much  finer  crops  when  the  same  species 
do  not  follow  in  immediate  sequence. f 

Attempts  have  been  made  at  various  times  to  explain  this  pheno- 
menon. It  was  at  first  thought  that  different  species  of  vegetables 
required  a  particular  nutriment ;  but  it  was  soon  perceived  to  be 
otherwise,  and  that  the  organs  of  each  plant  derived  the  necessary 
juices  from  substances  which  cone  (r  in  the  nutrition  of  vegetables 

♦  Thaer,  Africttlture  ral»oiui*e.  t  Wd. 


ROTATION.  345 

generally.  In  effect,  plants  the  most  opposite  in  botanical  character 
and  properties,  alimentary  as  well  as  poisonous,  will  live  and  flourish 
on  the  same  mound  of  earth,  and  with  the  same  manure.  Moreovei 
these  plants  reciprocally  withdraw  nourishment  from  one  another, 
which  could  not  occur  did  each  species  need  different  elements  of 
nutrition.* 

When  it  was  taken  for  granted  that  the  organs  of  plants  elaborate 
a  common  nourishment  derived  from  the  manure,  then  vegetables  of 
diverse  organizations  were  supposed  endued  with  the  faculty  of 
searching  at  different  depths  for  the  nutritive  matter  contained  in  the 
soil,  by  reason  of  a  more  or  less  considerable  extension  and  develop- 
ment of  their  roots.  This  served  to  explain  hour  a  plant  with  long 
and  perpendicular  roots  could,  as  a  sequel  to  corn,  derive  benefit 
from  manure  situate  in  the  undermost  layers  of  ploughed  land.  It 
is  possible  that  an  action  of  this  kind  may  take  place  under  certain 
circumstances,  but  the  explanation  can  never  be  generally  re- 
ceived. 

Another  explanation  of  the  necessity  for  alternate  crops  is  based 
upon  properties  assigned  to  the  excretions  of  the  roots,  as  compared 
to  animal  excrements. 

The  excretion  of  roots,  first  observed  by  Brugman  in  the  Viola 
arvensis,f  has  been  confirmed  by  the  recent  observations  of  M.  Ma- 
caire.  This  physiologist  obtained  the  matter  exuded  from  certain 
plants  by  keeping  their  roots  in  water  ;  but,  strange  to  say,  could  not 
discover  it  in  silicious  sand  in  which  certain  vegetables  had  been 
grown. I  I  myself  likewise  failed  in  detecting  sensible  traces  of 
organic  matter  in  sand  which  had  served  as  soil  during  several 
months  to  wheat  and  clover  ;  a  result  which  renders  the  fact  of 
radicular  excretion  doubtful.  The  excretion  consequent  upon  im- 
mersion in  water  is  perhaps  the  effect  of  disease. 

Be  that  as  it  may,  upon  the  assumption  of  the  excretion  from 
roots,  Messrs.  Von  Humboldt  and  Plenck  have  explained  the  cause 
of  the  attractions  and  repulsions  of  certain  plants.  §  More  recently 
M.  de  Candolle  has  reproduced  this  idea  as  the  basis  of  a  theory  of 
rotation  of  crops.  If  it  be  supposed,  in  fact,  that  the  excretion  from 
the  roots  represents  vegetable  excrements,  it  may  be  easily  imagin- 
ed that  these  excretions  once  deposited  in  the  soil  may  be  as  pre- 
judicial to  the  plant  which  produced  them  as  would  be  the  excrement 
of  an  animal  presented  to  it  as  food.  On  the  other  hand,  by  change 
of  species,  the  plant  newly  implanted  may  profit  by  the  excretions  of 
the  preceding  crop,  absorbing  them  as  nourishment.  This  ingenious 
hypothesis  is  deficient  in  the  groundwork,  inasmuch  as  the  fact  of 
radicular  excretion  is  not  sufficiently  established.  Again,  admitting 
the  excretion,  several  facts  concur  to  demonstrate  that  plants  may 
thrive  in  soil  charged  with  their  dwn  excrements. 

The  culture  of  corn,  for  example,  may  proceed  uninterruptedly, 
as  we  find  in  the  triennial  rotation.     I  have  seen  in  the  table-lands 


*  De  Candolle,  t.  i.  p.  248.  t  Ibid.  t.  ii.  p.  1497. 

t  Ibid,  t  iu.  p.  1474.  $  De  Candolle,  t.  iii.  p.  J474 


846  ROTATION. 

of  the  Andes  wheat  fields,  which  had  yielded  excellent  cr:ps  annaa]- 
iy  for  more  than  two  centuries.  Maize  may  likewise  be  continually 
reproduced  upon  the  same  ground  without  inconvenienc-e :  this  fact 
is  well  known  in  the  south  of  Europe  ;  and  the  greater  portion  of 
the  coast  of  Peru  has  produced  nothing  else,  from  a  date  long  ante- 
rior to  the  discovery  of  America.  Further,  potatoes  may  come  again 
and  again  upon  the  same  soil  ;  they  are  incessantly  cultivated  at 
Santa-Fe  and  Quito,  and  nowhere  are  they  of  better  quality.  In- 
digo and  sugar-cane  may  be  brought  under  the  same  category.  In 
Europe  the  Jerusalem  artichoke  produces  constantly  in  the  same 
place.*  It  must  be  conceded,  that  if  all  these  plants  excrete  from 
their  roots,  their  excretions  are  not  of  such  a  nature  as  to  interfere 
with  the  progress  of  vegetation  of  the  species  producing  them. 

But  the  capital  objection  to  the  hypothesis  of  De  Candolle  is  this, 
that  it  would  be  very  remarkable  indeed  did  any  soluble  organic 
matter,  like  such  secretions,  not  putrefy  when  lying  in  the  ground 
In  a  word,  it  is  difficult  to  understand  how  it  should  resist  for  years, 
as  is  pretended,  the  decomposing  influence  of  heat  and  moisture  to« 
gether. 

That  there  is  no  absolute  necessity  for  alternation  of  crops  when 
dung  and  labor  can  be  readily  procured,  is  undeniable.  Never- 
theless, there  are  certain  plants  which  cannot  be  reproduced  upon 
the  same  soil  advantageously  except  at  intervals  more  or  less  re- 
mote. The  cause  of  this  exigence  on  the  part  of  certain  vegetables 
is  still  obscure,  and  the  hypotheses  propounded  for  clearing  it  up  far 
from  satisfactory. 

One  of  the  marked  advantages  of  alternate  cultures,  is  the  periodic 
cultivation  of  plants  which  improve  the  soil.  In  this  way  a  sort  ol 
compensation  is  made  for  exhaustion.  The  main  thing  to  be  secur- 
ed in  rotation  of  crops  is  such  a  system  as  shall  enable  the  husband- 
man to  obtain  the  greatest  amount  of  vegetable  produce  with  the 
least  manure,  and  in  the  shortest  possible  time.  This  system  cao 
be  alone  realized  by  employing  in  the  course  of  rotation  those  plants 
which  draw  largely  upon  the  atmosphere. 

The  best  plan  of  rotation  in  theory,  is  that  in  which  the  quantity 
of  organic  matter  obtained  most  exceeds  the  quantity  of  organic 
matter  introduced  into  the  soil  in  the  shape  of  manure.  This  does 
not  hold  quite  in  practice.  It  is  less  the  surplus  amount  of  organic 
matter  over  that  contained  in  the  manure,  than  the  value  of  this 
same  matter  which  concerns  the  agriculturist.  The  excess  required, 
and  the  form  in  which  it  should  be  produced,  must  vary  widely  ac- 
cording to  locality,  commercial  demand,  and  the  habits  of  people, 
considerations  wholly  apart  from  theoretical  provisions.     One  point 

*  To  this  list  might  be  added,  according  to  the  recent  researches  of  M.  Braconnot, 
ihe  bay-rose  with  double  flowers,  and  Papaver  somniferum.  That  distinguished 
chemist  terminates  his  memoir  as  follows  :  "  My  experiments  are  unfavorable,  as  may 
be  perceived,  to  the  theory  of  rotation  of  cops  based  on  the  excretions  of  the  roots. 
These  excretions  if  really  occurring  in  the  lormal  state  are  so  obscure  and  little  known 
as  to  lead  to  the  inference  that  the  general  system  of  rotations  must  be  referred  ta 
some  other  source."  (Recherches  sur  I'influence  des  plantes  sur  le  sol,  Annales  d« 
Chimie  t  Ixxii.  p.  27.) 


ROTATION.  847 

in  theory  that  should  agree  with  practice  is  this,  that  in  no  case  is  it 
possible  to  export  more  organic  matter,  and  particularly  more  azo- 
tized  organic  matter,  than  the  excess  of  the  same  matter  contained 
in  the  manure  which  is  consumed  in  the  course  of  the  rotation.  By 
acting  upon  another  presumption  the  productiveness  of  the  soil  would 
be  infallibly  lessened. 

This  irrefragable  condition  as  to  the  term  of  exportation  from  a 
farm  suggests  some  critical  remarks  upon  sundry  notions  lately  pro- 
mulgated. The  manufacture  of  beet-root  sugar  is  an  instance. 
European  agriculture  may  probably  derive  certain  advantages  from 
this  modern  branch  of  industry,  although  these  have  been  mu<^h 
overrated  by  certain  speculators,  who  contend  that  sugar  may  thus 
be  obtained  through  rotation  of  crops  without  lessening  the  other 
produce  of  the  domain  ;  so  that  the  sugar  constitutes  an  additional 
source  of  income.     This  seems  to  me  erroneous. 

If  an  estate  yields  annually  100  tons  of  beet-root  for  the  support 
of  cattle,  their  number  must  be  diminished  if  the  root  is  to  he  used 
for  making  sugar.  The  organic  matter  of  the  sugar  extracted  there- 
from, is  just  so  much  nourishment  withheld  from  the  cattle.  To 
assert  the  contrary  would  be  equivalent  to  saying  that  potatoes  grown 
upon  a  couple  of  acres  of  land,  and  submitted  to  the  process  of  dis- 
tillation before  being  employed  as  fodder,  would  feed  as  many  animals 
as  if  eaten  directly  :  assuredly,  the  organic  principles  of  the  potato 
converted  into  alcohol  are  lost  as  regards  nutrition. 

This  does  not  imply  that  the  manufacture  of  indigenous  sugar, 
and  of  potato  spirit,  is  less  productive  than  breeding  and  fattening 
cattle.  My  sole  object  is  to  show  that  only  a  limited  quantity  of 
organic  matter  can  be  advantageously  exported  from  an  agricultural 
establishment.  It  must  depend  upon  local  and  commercial  circum- 
stances whether  this  is  to  be  exported  in  the  form  of  sugar,  corn, 
spirit,  or  butcher-meat. 

The  above  statement  is  in  apparent  contradiction  with  generally 
received  notions.  Many  persons  believe  that  the  manufacture  of 
sugar,  instead  of  injuring,  is  favorable  to  the  breeding  of  cattle.  It 
appears,  from  a  Parliamentary  return  on  this  subject,  in  1836,  that 
in  certain  estates  where  sugar  was  made,  the  number  of  animals 
was  increased ;  the  numerical  results  are  no  doubt  exact,  but  this 
augmentation  in  cattle  is  rather  to  be  ascribed  to  an  improved  mode 
of  farming  than  to  the  manufacture  of  sugar.  In  establishments 
where  the  triennial  rotation  with  fallow  was  pursued,  a  rotation  of 
four  or  five  years  with  clover  and  weed-destroying  plants  has  been 
introduced  ;  so  that  it  is  by  no  means  to  be  wondered  at,  that  inde- 
pendently of  beet-root,  there  should  have  been  a  considerable  increase 
in  other  things.  The  introduction  of  this  root,  where  it  was  not 
formeny  grown,  is  of  itself  an  important  melioration.  But  in  highly 
cultivated  countries,  where  the  most  productive  rotations  have  been 
long  followed,  the  extraction  of  sugar  would  not  effect  such  advan- 
tageous changes  as  those  announced  in  the  above  return.  If  at 
Bechelbronn  a  time  should  ever  come,  and  at  present  it  seems  far 
distant,  when.it  wduld  be  deemed  expedient  to  make  sugar  from  the 


S48  ELEMENTS    OF   CROPS. 

beet  there  grown  it  would  certainly  be  requisite  to  diminish  the 
number  of  cattle,  or  else  to  annex  more  meadow  land.  It  is  only 
indirectly,  therefo  e,  that  the  manufacture  of  home-sugar  can  pro- 
mote the  breeding  of  cattle,  and  so  prove  serriceable  to  agriculture. 

From  the  definition  given  by  me  of  the  most  advantageous  course 
of  crops,  theoretically  considered,  it  may  be  inferred  how  closely  the 
study  of  rotations  is  connected  with  that  of  the  exhaustion  of  the 
soil.  Hence,  to  discuss  the  value  of  divers  rotations,  we  must,  in 
consonance  with  theory,  compare  the  quantity  of  organic  matter  in 
a  sequence  of  crops,  with  that  in  the  manure  expended  upon  them. 

From  a  well-managed  farm,  where  for  a  series  of  years  an  invari- 
able system  of  culture  has  been  steadily  pursued,  we  must  look  for 
data.  This  I  have  done,  as  regards  Bechelbronn,  determining  by 
analysis  the  composition  of  the  manures  and  crops,  and  also  of  the 
more  ordinary  kinds  of  fodder  or  food.  For  a  long  time,  a  five 
years'  rotation  has  been  there  adopted  in  the  following  order : 

1st  year.— Potatoes  or  beet-root  manured. 

2d  year.— Wheat  sown  the  autumn  of  the  first  year ;  clover  interposed  In  the  spring. 

3d  year. — Trefoil  (clover)  two  crops ;  the  third  crop  ploughed  in  or  smothered. 

4th  year. — Wheat  on  the  clover-break,  turnips  after  the  wheat. 

5th  year. — Oats. 

The  crop  of  oats  which  ends  the  rotation  is  generally  scanty. 
The  soil  is  then  brought  back  to  the  point  of  fertility  which  it  had 
before  being  dunged  ;  and  it  is  known  by  experience  that  it  will  not 
now  yield  a  crop  of  any  value. 

I  now  proceed  to  detail  the  analyses  of  the  different  substances 
which  enter  into  the  rotation,  indicating  at  the  same  time  the  average 
produce  per  acre. 

POTATOES. 

In  the  rather  strong  soil  of  Bechelbronn  one  acre  produces  upon 
an  average  about  105  cwts.  of  potatoes.  This  is  below  the  ordinary 
rate  of  Alsace,  where  the  crop  amounts  to  from  155  to  165  cwts. 
per  acre.     The  leaves  and  stems  are  left  upon  the  ground. 

A  potato  was  cut  in  two,  in  order  to  subject  it  to  analysis  with  a 
proportional  part  of  the  peel.  The  half  weighed  335.2  grs.  Stove- 
dried  and  reduced  to  flour,  it  weighed  289.3  grs.  By  absolute  desic- 
cation in  vacuo,  at  a  temperature  of  230°  F.  it  was  found  that  one 
of  moist  tuber  became  0.241  ;  15.4  grs.  left  of  ash  0.039. 

The  average  quantity  of  azote  is  1.2.  In  1836,  I  found  1.8  of 
azote.  This  notable  difTerence,  perhaps,  depends  on  the  analysis 
not  having  been  made  immediately  after  the  harvest ;  or  it  may  be 
partly  du3  to  meteorological  influences.  To  convince  myself  that  it 
did  not  depend  upon  any  error  of  analysis,  I  examined  anew  the 
potato  of  1836,  preserved  in  the  farinaceous  state  :  it  yielded  1.8 
of  azote      I  shall,  therefore,  reckon  the  azote  at  1.5  : 

I.  II. 

Carbon 43.72  43.40 

Hydrogen 6.00  5.60 

Oxygen 44.88  45.60 

Azote 1.50  1.50 

Aih 3. 00  3.90 


ELEMENTS   OF   CROPS.  349 


WHEAT. 

I  analyzed  the  grain  gathered  in  1837 :  one  of  wheat,  dried  in 
vacuo  at  230°  F.  was  reduced  to  0.885 ;  one  of  dry  wheat  left  of 
ash  0.0243  : 

Carbon 46.10 

Hydrogen 5.80 

Oxygen 43-40 

Azote 2.29 

Ash 2.43 

100.00 

The  mean  produce  in  wheat  at  Bechelbronn  varies  from  20^  to 
22  bushels  per  acre  ;  this  variation  depends  on  the  drill  crop  which 
commences  the  rotation.  After  potatoes  the  average  crop  is  19^ 
bushels;  after  beet-root,  17  bushels;  on  clover-breaks  it  is  24  bushels. 
The  average  weight  of  the  grain  is  63  lbs.  per  bushel. 

WHEAT-STRAW. 

I  estimate  the  proportion  of  the  produce  in  grain  to  that  in  straw, 
as  44  to  100. 

One  of  straw  completely  dried  in  vacuo  at  230°  F.  becomes  0.740; 
one  of  dry  straw  leaves  0.0697  of  ash  : 

1.  n. 

Carbon 48-48  48-38 

Hydrogen 5.41  5.21 

Oxygen 38.79  39.09 

Azote 0-35  0.35 

Ash 6-97  69.7 

100-00  100.00 

RED  CLOVER. 

Clover  delights  in  clayey  soils ;  it  thrives  generally  in  good  wheat 
lands  ;  in  light  and  sandy  ground  it  gets  bare  and  frosted.  During 
its  growth,  it  always  requires  the  shelter  of  some  other  plant.  For 
this  reason,  in  spring,  it  is  generally  sown  among  wheat,  which  is 
put  in  the  preceding  autumn,  or  barley  sown  the  same  spring.  We 
generally  give  from  11  to  14  lbs.  of  seed  per  acre.  Clover  is  mow- 
ed the  second  year,  as  it  is  coming  into  flower ;  but  when  it  is  not 
to  be  consumed  as  green  fodder,  the  mowing  may  take  place  before 
the  flowering  ;  this  is  required  from  the  difficulty  of  making  it  into 
hay.  In  fact,  in  the  process  of  drying  clover,  there  is  great  risk  of 
losing  part  both  of  the  leaves  and  flower ;  besides,  the  drying  always 
requires  a  considerable  time,  during  which  the  clover  runs  the  chance 
of  being  damaged  by  rain,  and  clover  hay-making  is  almost  im- 
practicable in  wet  weather.  Schwertz  proposed  to  dry  the  clover 
on  a  sort  of  parrot-perches  stuck  into  the  ground.  These  supports 
are  but  eight  feet  high,  and  capable  of  bearing  a  load  of  2  cwt.  of 
green  fodder,  mowed  twenty-four  hours,  and  already  withered.  This 
method,  as  I  have  seen  it  practised  in  the  Duchy  of  Baden,  answers 
well,  but  there  is  considerable  cost  for  manual  labor,  and  in  the  first 
instance  for  perches.     Schwertz  reckons  that  2  cwts.  of  green  clover 

30 


350  ELEMENTS    OF    CROPS. 

yield  48  lbs.  of  hay.  The  relation  of  green  to  dry  fodder  varies 
with  the  age  of  the  plant,  and  the  meteorological  circumstances 
under  which  it  has  grown.  Subjoined  is  the  result  of  some  experi- 
ments which  I  performed  on  the  making  of  clover  hay  : 

1  ton  of  clover  in  flower,  2d  year    (1841)  afforded  in  hay  7  cwts. 

1  ton  of  clover  1st  year  (1842)        "  4  cwts.  2  qrs.  24  lbs. 

The  average  produce  of  this  fodder  reduced  to  hay  at  Bechel- 
bronn  is  41  cwts.  3  qrs.  per  acre. 

One  of  clover  hay,  after  complete  desiccation,  weighed  0.790 ; 

one  of  dry  hay  left  0.078  of  ash  : 

I.  n. 

Carbon 47.53  47.19 

Hydrogen 4.69  5.33 

Oxygen 57.96  37.66 

Azote 2.06  2-06 

Ash 7.76  7.76 

100.00  100.00 

TURNIPS. 

When  turnips  are  cultivated  as  a  second  crop,  as  after  rye  or 
wheat,  the  produce  is  very  uncertain.  Attempts  are  occasionally 
made  to  raise  them  after  wheat  which  has  followed  clover. 

When  cultivated  on  fresh  manured  soil,  the  produce  is  considera- 
ble ;  in  some  places  it  amounts  to  from  28  to  33  tons  per  acre  ;  but 
as  a  second  crop,  we  only  obtain  upon  an  average  7|  tons  per  acre. 
This  crop  is  only  counted  as  a  half-crop  in  the  general  produce  of 
the  rotation. 

Turnip  is  the  most  watery  root  I  have  examined.  A  slice  weigh- 
ing 2  oz.  17  dwts.  dried  in  the  stove,  was  reduced  to  4  dwts.  After 
thorough  desiccation,  one  of  turnip  weighed  0.075  ;  consequently 
the  root  contains  92.5  per  cent,  of  water  ;  one  of  dried  turnip  incin- 
erated, left  0.0758  of  ash  : 

I.  n. 

Carbon 42.80  49.93 

Hydrogen 5.54  5.61 

Oxygen 42-40  42-20 

Azote 1-68  1.68 

Ash 7-58  7.58 

100.00  100-00 

OATS. 

As  this  grain  closes  the  rotation,  the  produce  is  not  great.  The 
average  crop  is  37  bushels  per  acre,  at  the  weight  of  33^  lbs.  per 
bushel  ;*  one  of  oats  conrpletely  dried  weighs  0.792  ;  one  of  dried 
•ats  leaves  0.0398  of  ash  ; 

I.  n. 

Carbon 50-32  51.09 

Hydrogen 6.32  6.44 

Oxygen 37.14  36.25 

Azote 2.24  2.24 

Ash 3-98  3-98 

100.00  100-00 

•  This  is  but  a  light  weight  for  a  bushel  of  oats.— Ejf«.  E». 


ELEMENTS  OF  CROPS.  851 

OAT  STRAW. 

Oat  straw  is  estimated  at  about  15  cwts.  per  acre  ;  one  part 
becomes,  when  dried  in  vacuo,  0.713  ;  one  part  burned  leaves  0.0509 
of  ash  • 

Carbon 49.93  50-25 

Hydrogen 5.32  5.48 

Oxygen 39.28  38.80 

Azote 0.38  0.38 

Ash      5.09  5.09 

100.00  100.00 

riELD  BEET  OR  MANGEL-WURZEL. 

Or  a  freshly  manured  soil,  the  average  produce  of  beet  at  Bechel« 
bronn  is  10  tons,  15  cwts.  1  qr.  per  acre.  The  worst  crops  do  not 
fall  below  5  tons,  2  cwts.  1  qr.  14  lbs.,  and  the  best  do  not  exceed 
16  tons,  7  cwts.  1  qr.,  results  which  I  took  occasion  to.observe  varied 
sensibly  from  those  obtained  in  different  places.  I  stated  that 
Schwertz  and  Thaer  make  the  average  14  tons,  14  cwts.  2  qrs.  16 
lbs.  Moelinger,  after  taking  the  mean  of  ten  years,  adopts  11  tons, 
1  cwt.  3  qrs.  6  lbs.  At  Roville,  M.  de  Dombasle  speaks  of  7  tons, 
3  cwts.  26  lbs.  as  the  mean  of  seven  years. 

At  Bechelbronn,  the  leaves  of  the  beet  are  not  given  to  cattle  ; 
thpy  are  left  upon  the  ground.  A  piece  of  beet-root  weighing  1  oz. 
16  dwts.  was  reduced  to  4^'^^,  say  5  dwts.  after  being  stove  dried. 
After  complete  desiccation,  at  230°  F.  one  part  of  root  became  0. 122  ; 
one  part  of  root  left  upon  incineration  0.0624  of  residuum  : 

Carbon 42.75  42.93 

Hydrogen 5.77  5.94 

Oxygen 43.58  43.33 

Azote 1.66  1.66 

Ash 6.24  6.24 

100.00  190.00 

RYE. 

Rye  is  seldom  introduced  into  the  rotation  at  Bechelbronn.  They 
reckon  its  produce  at  26  bushels  per  acre,  when  it  has  had  a  sup- 
plementary dose  of  manure.  The  bushel  weighs  fully  58  lbs.  I 
have  taken  the  proportion  of  grain  to  straw  as  45  is  to  100.  One 
part  of  rye,  dried  at  230°  F.  weighed  0.834  ;  one  part  incinerated 
left  0.0237  of  ash  : 

1.  n.  in. 

Carbon 46.35  4.5.72  46.38 

Hydrogen 5.38  5.70  5.74 

Oxygen 44.21  44.52  43.82 

Azote 1.69  1.69             1.69 

Ash 2.37  2.37  2.37 

100.00         100.00         100.00 
RYE-STRAW. 

One  part  of  straw,  completely  dried,  weighed  0.813  ;  one  part  of 
which,  incinerated,  left  0.0368  of  ash  : 


852  ELEMENTS    OF   CROPS. 

Carbcn 49.88 

Hydrogen 5.58 

Oxygen 40..')6 

Azote.. 0.30 

Ash..... 3.68 

100.00 

WHITE  PEAS 

Raised  on  manured  land  yielded  16  buihels  per  acre,  weighing 
fully  62  lbs.  per  bushel.  One  part  of  peas,  after  complete  desicca- 
tion, weighed  0.914  ;  one  part  of  dried  peas  left  of  ash  0.0314  : 

I.  n. 

Carbon 46.06  46.94 

Hydrogen 6.09  6.34 

Oxygen 40.53  39.50 

Azote 4.18  4.18 

Ash 3.14  3.14 

100.00  100.00 

PEA  STRAW. 

One  acre  of  peas  produces  about  22  or  23  cwts.  of  straw  ;  one  part 
of  the  straw  after  desiccation  weighed  0.802  ;  one  part  after  incine- 
ration 0.1132  : 

Carbon 45.80 

Hydrogen 5.00 

Oxygen 35.57 

Azote ••••  2.31 

Ash 11.32 

100.0C 

JERUSALEM  POTATO  OR  ARTICHOKE. 

In  Alsace,  Jerusalem  artichokes  are  always  grown  on  one  and 
the  same  piece  of  land,  which  is  manured  every  two  years.  At 
Bechelbronn,  on  a  somewhat  shallow  soil,  the  produce  per  acre 
amounts  to : 

Tubers 10  tons 

Dry  stems Hi  cwts. 

A  tuber  which  weighed  on  being  taken  from  the  ground  1  oz. 
IS^nr  dwts ,  weighed  ^  dwts.  after  it  was  dried  in  the  stove.  Afler 
absolute  desiccation,  one  part  was  reduced  to  0.208  ;  one  portion  of 
the  dry  tuber  left  0.0594  after  incineration  : 

n. 

Carbon 4-12  43.62 

Hydrogen 5.91  5.80 

Oxygen 43.56  43.07 

Azote 1.57  1.57 

Ash 5.94  5.94 

100.00  100.00 

DRIED  STEMS  OF  JERUSALEM  ARTICHOKES. 

These  stems  had  stood  through  the  winter  where  they  grew,  and 
were  almost  wholly  composed  of  pith.  One  part  after  desiccation 
weighed  0.871 :  one  part  left  of  ash  0.0276. 


ELEMENTS    OF    CROPS. 


358 


Carbon 45.68 

Hydrogen 5.43 

Oxygen 45.72 

Azote 0.43 

Ash 2.76 

100.00 

I  fear  that  in  this  analysis  the  carbon  and  azote  are  rated  too  low. 

I  have  collected  in  two  tables  the  results  of  the  analyses  as  detail, 
ed  above.  The  first  exhibits  the  quantity  of  dry  matter  and  moisture 
contained  in  each  specimen  ;  the  other,  the  elementary  composition. 
On  careful  examination  of  the  numbers  given  in  the  second  table, 
certain  substances  will  be  found  very  analogous  in  composition.  If 
the  ashes  be  deducted,  the  analogy  becomes  complete  ;  for  many 
substances  differing  widely  both  in  character  and  properties,  never- 
theless appear  to  possess  the  same  composition  ;  a  fact  which  I  do 
not  undertake  to  explain. 

TABLE    OF    THE    PROPORTIONS    OF    WATER    CONTAINED    IN    DIFFERENT 
SUBSTANCES. 

Substancet.  Dry  matter.  Water. 

Wheat 0.855  0.145 

Rye 0.834  0.166 

Oats 0.792  0.208 

Wheat-straw 0.740  0.260 

Rye-straw 0.813  0.187 

Oat-straw 0.713  0287 

Potato 0.241  0.759 

Field-beet 0.122  0.878 

Turnip 0.075  0.925 

Jerusalem  potato 0.208  0.792 

Peas 0.914  0.086 

Pea-straw 0.882  0.118 

Clover-hay 0.790  0.210 

Jerusalem  potato-stems  •  •  • .  • 0.871  0.129 

COMPOSITION    OF    THE    SAME    SUBSTANCES   DRIED    IN   VACUO    AT   SSO* 

FAHR. 


SUBSTANCES. 

Ashes  included. 

Ashes  deducted. 

1 

i 
>« 

1 

S 

so 

< 

1 

d 

X 

3 

•< 

\Y^gjit        

46.1 
46.2 
50.7 
48.4 
49.9 
50.1 
44.0 
42.8 
42.9 
43.3 
46.5 
45.8 
47.4 

45.7 

05.8 
05.6 
06.4 
05.3 
05.6 
05.4 
05.8 
05.8 
05.5 
05.8 
06.2 
05.0 
05.0 

05.4 

43.4 
44.2 
36.7 
38.9 
40.6 
39.0 
44.7 
43.4 
42.3 
43.3 
40.0 
35.6 
37.8 

45.7 

02.3 
01.7 
02.2 
00.4 
00.3 
00.4 
01.5 
01.7 
01.7 
01.6 
04.2 
02.3 
02.1 

00.4 

02.4 
02.3 
04.0 
07.0 
03.6 
05.1 
04.0 
06.3 
07.6 
06.0 
03.1 
11.3 
07.7 

02.8 

47.2 
47.3 
52.9 
52.1 
51.8 
52.8 
45.9 
45.7 
46.3 
46.0 
48.0 
51.5 
51.3 

47.0 

06.0 
05.7 
06.6 
05.7 
05.8 
05.7 
06.1 
06.2 
06.0 
06.2 
06.4 
05.6 
05.4 

05.6 

44.4 
45.3 
38.2 
41.8 
42.1 
41.1 
46.4 
46.3 
45.9 
46.1 
41.3 
40.3 
41.1 

47.0 

02.4 
01.7 
02.3 
00.4 
00.3 
00.4 
01.6 
01.8 
01.8 
01.7 
043 
02.6 
02.2 

00.4 

Rve 

Wheat- straw  ... 

Rye-straw 

Oat-straw 

Field-beet 

Turnip 

Jerusalem  potato 

Pea-straw 

Clover-hay 

Jerusalem    pota- 
to-stems   

30* 


854  ELEMENTS   OF   MANFRE. 


RELATIONS  OF  MANURES  TO  CROPS. 


The  manure  employed  at  Bechelbronn  is  what  is  commonly  called 
farm-yard  dung,  a  compost  made  up  of  the  excrements  of  horses, 
oxen,  and  straw  litter  impregnated  with  urine.  The  dung  of  fowls 
and  pigeons,  and  the  sweepings  of  the  yard,  are  sometimes  applied 
to  special  purposes.  The  animals  whose  excrements  form  the  dung" 
which  I  have  examined  were  horses,  oxen,  and  swine. 

The  manure  is  put  upon  the  ground  when  it  has  undergone  fer- 
mentation in  the  heap  :  it  is  manure  half-made  :  the  straw  litter  is 
not  entirely  decomposed,  but  is  soft  and  filamentous ;  in  this  state 
manure  retains  a  great  deal  of  moisture. 

DESICCATION    OF    HALF-MADE    OR   HALF-DECAYED    MANURE. 
EXPERIMENT    I. 

A  quantity  of  manure  prepared  during  the  winter  of  1837-1838, 
which  in  the  state  in  which  it  was  being  put  on  the  ground,  weighed 
257  lbs  after  it  had  been  dried  so  as  to  be  easily  reduced  to  powder, 
weighed  57  lbs.  The  loss  of  water  was  therefore  about  77.3  in  100 
This  number  comes  very  near  the  estimate  of  several  German 
agriculturists,  who  reckon  the  moisture  in  farm-yard  dung  at  75  per 
cent.  Still  this  loss  does  not  represent  the  whole  of  the  water  ;  for 
after  desiccation  at  212°  F.  the  57  lbs.  weighed  54  lbs.  In  fine, 
after  desiccation  in  vacuo,  at  230°  F.  it  was  found  that  one  part  of 
stove-dried  manure  lost  0.039.  Thus  the  manure  parted  in  totality 
with  79.62  per  cent,  of  water,  and  contained  in  consequence  20.4  of 
dry  substance. 

EXPERIMENT    II. 

Of  the  manure  prepared  in  the  winter  of  1838-1839,  220  lbs.  after 
being  chopped  and  dried  weighed  56  lbs.  One  part  of  this  manure 
was  reduced  in  dry  vacuo  at  a  temperature  of  230°  F.  to  0.872.  The 
280  lbs.  would  therefore  have  weighed  when  dry  48  lbs. 

EXPERIMENT    III. 

Of  the  manure  prepared  during  the  summer  of  1839,  660  lbs. 
weighed  after  desiccation  151  lbs.  ;  of  this  dry  manure  reduced  to 
powder,  one  part  lost  by  desiccation  in  vacuo  at  230°  F.  0.1461. 

The  151  lbs.  would  therefore  have  lost  22  lbs.  ;  consequently  the 
660  lbs.  of  manure  contained  129  lbs.  of  dry  matter,  that  is,  19.64 
per  cent. 

Subjoined  is  a  summary  of  the  per  centage  of  dry  matter : 

First  experiment 20.4 

Second        "        22.2 

Third         ♦         19.6 

Average 20.7 

Moisture  (average) 793 

ANALYSES  OF  HALF-MADE  MANURES. 

I.  Manure  prepared  during  the  winter  of  1837-1838: 
Matter  0.5595,  gave  carbonic  acid  0.528,  water  0.157  :  C.  32.4,  H.  3.8^ 
Asote  1.7.— 1.0  gave  ashei  0.462. 


ELEMENTS   OF    MANURE.  355 

II.  Manure  prepared  during  the  winter  of  1837-1838 : 

Matter  0.575.  gave  carbonic  acid  0.676,  water  0.212  :  C  32.5,  H.  4.1, 
.A.zote  1.69.— 1.000  gave  ashes  0.357. 

III.  Manure  prepared  during  the  winter  of  1837-1838: 

Matter  0.567,  gave  carbonic  acid  0.791,  water  0.232  :  C.  38.7,  H.  4.5, 
Azote  1.73.— 1.000  gave  ashes  0.264. 

IV.  Manure  prepared  during  the  spring  of  1838  : 

Matter  0.586,  gave  carbonic  acid  0.759,  water  0.308  :  C.  36.4,  H.  4.0, 
Azote  2.4.— 1.000  gave  ashes  0.381. 

V.  Manure  prepared  during  the  spring  of  1839  : 
Matter  0.445,  gave  carbonic  acid  0.643,  water  0.171 :  C.  40.0,  H.  4.3, 

Azote  2.4.-1.000  gave  ashes  0.257. 

VI. 

Matter  0.427,  gave  carbonic  acid  0.543,  water  0.150  :  C.  34.7,  H,  3.9. 
"     0.427,        "        "  0.530,      "      0.127  :  "  34.3,  "  4.8, 

Azote  2.0.-1.000  gave  ashes  0.315. 

COMPOSITION  OP  THE  MANURES  ANALYZED. 

Carbon.         Hydrogen.  Oxy^^en.  Azote.       Salts  and  earthly 

I.  32.4  3.8  25.8  1.7  36.5 

II.  32.5  4.1  26.0  1.7  35.7 

III.  38.7  4.5  28.7  1.7  26.4 

IV.  36.4  4.0  19.1  2.4  38.1 
V.  40.0  4.3  27.6  2.4  25.7 

VI.  34.5  4.3  27.7  2.0  31.5 

Mean    .     .     .    35.8  4.2  25.8  2.0  32.2 

In  all  these  analyses,  the  combustion  was  promoted  by  the  addi- 
tion of  chlorate  of  potash ;  some  oxide  of  antimony  was  likewise 
added.     The  carbonic  acid  of  the  ash  was  determined  and  struck  off. 

The  measure  of  dung  in  use  at  Bechelbronn  is  the  wagon  drawn 
by  four  horses.  After  repeated  weighings  it  was  found  that  this 
measure  contains  nearly  1  ton,  15  cwts.  2  qrs.  23  lbs.  of  moist  material, 
or  7  cwt.  1  qr.  15  lbs.  if  that  be  computed  dry.  The  first  course  of 
the  rotation  receives  27  loads  of  this  manure,  weighing  about  48  tons, 
14  qrs.  5  lbs.,  equivalent  to  9  tons,  19  cwts.  0  qr.  2  lbs.  of  dry  ma- 
nure.* 

The  preceding  analyses  show  that  this  charge  of  manure,  which 
is  to  fertilize  the  soil  during  the  course  of  the  rotati/>n  ^five  years) 
contains  : 

Carbon .- 8027  lbs. 

Hydrogen 925 

Oxygen 5767 

Azote 447 

Salts  and  earth 7188 

22355 

Such  are  the  principles  vi4iich  together  form  the  organic  matter 
that  is  to  be  consumed  and  in  major  part  assimilated  by  the  crops 

»  I  presume  that  the  quantity  above  specified  is  that  which  is  laid  on  the  French 
hectare,  equal  to  2.4  acres  English.  To  get  at  the  quantity  laid  on  per  acre,  it  would 
therefore  be  necessary  to  divide  by  2  4-10  :  Thus  48  tons,  14  cwts.  5  lbs.  per  hectare 
will  be  equal  to  20  ton's,  1  cwt.  3  qrs.  per  English  acre.— Enq.  Ed. 


356  relax:,  ns  of  elements 

grown.  I  say  partly,  because  I  do  not  believe  that  the  whole  or 
ganic  matter  necessarily  enters  into  the  constitution  of  the  plants 
which  spring  up  during  the  rotation  ;  no  doubt  a  considerable  por- 
tion of  the  manure  is  lost  through  spontaneous  decomposition,  or  is 
carried  away  by  the  rain  ;  and  another  portion  may  remain  a  long 
time  dormant  in  the  soil,  to  act  as  a  fertilizer  at  a  more  or  less  dis- 
tant period  ;  just  as  in  the  present  rotation  the  manure  formerly  in- 
troduced co-operates  with  that  recently  added.  One  thing  is  certain, 
viz.,  that  the  proportion  of  manure  indicated  is  essential  for  a\erage 
crops  ;  by  diminishing  it  the  produce  is  necessarily  lessened.  Last- 
ly, it  is  proved  that  after  the  rotation  the  crops  have  consumed  the 
manure,  and  the  earth  will  not  yield  its  increase  unless  a  fresh  quan- 
tity be  added. 

I  now  proceed  to  consider  the  relation  subsisting  between  the 
quantity  of  organic  matter  buried  in  the  soil  as  manure,  and  what  is 
recovered  in  the  crops.  In  this  way  the  respective  proportions  of 
elementary  matter  which  various  crops  derived  from  the  air  and  the 
soil,  may  be  determined  approximately,  and  a  knowledge  obtained 
of  those  rotations  which  least  exhaust  the  land,  or  in  other  words, 
which  obtain  from  the  atmosphere  the  largest  amount  of  organic 
matter. 

The  rotations  set  down  in  Tables  I.  and  II.  are  those  definitively 
adopted  at  Bechelbronn,  and  throughout  the  greater  part  of  Alsace. 
These  two  rotations,  which  differ  only  in  the  hoed  crop  introduced, 
potatoes  in  one,  beet-root  in  the  other,  are  almost  identical ;  nearly 
the  same  quantity  of  dry  matter  being  produced  per  acre,  and  nearly 
the  same  quantity  of  organic  material  withdrawn  from  the  atmo- 
sphere. 

The  rotation  No.  3  was  introduced  by  Schwertz  at  Hohenheim ; 
theoretically,  it  is  one  of  the  most  advantageous ;  it  was  tried  at 
Bechelbronn  but  abandoned,  because,  from  meteorological  causes, 
peas  and  vetches  fail  frequently. 

Table  No.  4,  shows  the  triennial  rotation  with  manured  fallow ; 
this  is  disadvantageous  in  point  of  theory.  The  organic  consti- 
tuents of  the  crop  exceed  but  little  those  of  the  manure.  Suppos- 
ing that  even  the  whole  of  the  straw  were  converted  into  manure, 
the  farmer  would  still  be  compelled  to  procure  manure  from  abroad, 
in  compensation  for  the  out-going  of  wheat.  It  is  thus  obvious  why 
triennial  rotation  always  requires  a  great  deal  of  meadow  land. 

In  table  No.  5,  the  result  of  the  continuous  cultivation  of  Jerusa- 
lem artichokes  is  given.  At  Bechelbronn  these  are  dressed  every 
two  years  with  about  ten  loads  of  dung  per  acre.  Upon  an  average 
20  tons  of  tubers  and  about  2  tons  of  woody  stems  are  gathered  in 
the  course  of  two  years.  It  will  be  perceived  from  perusal  of  this 
table,  that  the  culture  of  Jerusalem  artichokes  presents,  theoretical- 
ly, considerable  advantages.  The  organic  matter  of  the  crop  greatly 
exceeds  that  of  the  manure.  Moreover,  in  Alsace,  where  it  is  very 
common,  it  is  held  to  be  most  productive.  Still,  the  organic  matter 
of  the  stems  must  be  taken  into  account,  which,  practically  speak- 
ing, are  nearly  worthless. 


IN    CROPS    AND    MANURE. 


357 


Table  No.  6  comprises  the  data  relative  to  a  quadrennial  rotation, 
adopted  by  M.  Crud,  and  in  which  are  grown  successively :  1st. 
Potatoes  or  beet-root.  2d.  Wheat.  3d.  Red  clover.  4th.  Wheat. 
The  first  sowing  is  dressed  with  about  18  tons  of  half-wasted  farm- 
yard dung.  The  gain  in  organic  matter  obtained  by  this  rotation 
surpasses  that  of  the  preceding  ;  but  as  the  clover  crops  are  not  very 
sure  when  repeated  every  four  years,  M.  Crud,  for  reasons  which 
may  be  called  in  question,  follows  this  rotation  with  one  of  lucern, 
which  gets  a  fresh  supply  of  manure.  It  cannot  be  denied  that  lu- 
cern furnishes  a  great  mass  of  fodder,  and  in  this  respect  the  fertili- 
ty of  the  land  ought  to  be  vastly  enhanced,  were  this  consumed  on 
the  spot ;  but  I  can  discover  no  objection  to  the  renewal  of  clover, 
if  the  lucern  succeeds  so  well  as  M.  Crud  says  it  does.  From  too 
frequent  repetition,  farmers  have  gone  into  the  opposite  extreme  of 
cultivating  clover  only  every  five  or  six  years.  This  subject  offers 
an  important  field  for  research.  It  is  not  impossible  that  the  ill- 
success  depends  often  on  premature  mowing  of  the  clover  during 
the  first  year,  and  before  its  roots  have  acquired  sufficient  vigor. 
This  practice  has  been  abandoned  with  us  for  some  years,  and  there 
is  now  every  thing  to  assure  us  that  the  second  year's  crop  is  there- 
by secured. 

ROTATION  COURSE  No.  1. 


Years, 

Substances. 

Crops 
per  acre. 

Crops 
dry. 

Carbon. 

Hydro, 
gen. 

Oxygen. 

Azote. 

Salts 

and 

earths. 

1st 

2d 

3d 
4th 

5th 

Potatoes    .... 
Wheat      .... 
Wheat-straw     .    . 
Clover-huy    .    .    . 
Wheat      .... 
Wheat-straw     .    . 
Turnips  C2d  crop)  . 

Oat-stra*w'    !    *.    ! 

Manure  employed  . 
Difference     .    .    . 

lbs, 

'ii? 

2798 
1650 

1052 
1300 

1? 

975 
1176 

1244 

1002 
1750 

2832 

185 
75 
135 

lbs, 
1264 

99; 
458 

'SI- 
% 
i 

10 
5 

1 

li  1 

1! 

179 

1 

60 

37050 
4495 

16307 
9314 

10236 
3426 

891 
391 

6575 
2403 

229 
185 

^ 

6993 

6810 

500 

4172 

44 

a»3 

ROTATION  COURSE  No.  2. 


Years. 

Substances. 

Crops 
per  acre. 

Crops 
dry. 

Carbon. 

Hydro- 
gen. 

Oxygen, 

Azote, 

Salts 

and 

earths. 

Ist 

2d 

■     6th 

^K'"."™'.  : 

Wheat-straw    .    . 
Clover-hay  .    .    . 
Wheat     .... 
Wheat-straw    .    . 
Turnips    .... 

Oat-straw'    '.    '.    '. 

Total 

Manure  employed 

Difference    .    .    . 

lbs, 
2383 

fJ^ 

11675 
1520 
3456 

1630 

lbs, 

1827 

lbs. 
281 

'iii 
i 

'1 

135 

36 

lbs. 

1 

lbs, 

i 

7 
77 
30 
10 

^1 

'la 
,1 

1 
i 

60 

27224 
4495 

16018 
9314 

7505 
3426 

11 

6423 
2403 

231 
185 

S_ 

6704 

4079 

473 

4020 

46 

2024 

S53 


RELATIONS    OF    ELEMENTS. 


ROTATION     COURSE     No.    3. 


Yean. 

Substances. 

Crops 
per  acre. 

Crops 
dry. 

Carbon. 

Hyd-  J- 

gen. 

Oxygen. 

Azote. 

Salts 

and 

earths. 

lbs. 

lbs. 

lbs. 

lbs. 

lbs. 

lbs. 

lbs. 

1st 

Potatoes  .... 

11733 

2^ 

1244 

164 

1264 

42 

113 

2d 

Wheat     .... 

1231 

1054 

485 

61 

457 

24 

25 

W^heat-straw    .    . 

2;98 

2070 

1002 

110 

805 

8 

145 

3d 

Clover-hay  .    .    . 

4675 

3693 

1750 

185 

1396 

78 

284 

4th 

Wheat      .... 

1515 

1300 

75 

564 

30 

31 

Wheat-straw    .    . 

3456 

2558 

1238 

135 

995 

10 

179 

Turnips    .... 

8754 

656 

282 

36 

11 

50 

5th 

Peas (dunged)  .    . 

1001 

915 

425 

56 

366 

38 

28 

Pea-straw     .    .    . 

2558 

22.56 

1033 

112 

803 

255 

6th 

Rye 

1539 

1278 

590 

71 

565 

22 

30 

Rye-straw     .    .    . 
Total 

3420 

2780 

1387 

155 

1129 

« 

100 

148280 

21388 

10035 

1160 

8622 

323 

1240 

Manure  employed 
Difference     .    .    . 

148285 

11176 

4000 

470 

2883 

223 

3599 

10212 

6035 

690 

5739 

100 

2359 

ROTATION    COURSE    No.    4. 


Years. 

Substances. 

Crops 
per  acre. 

Crops 
dry. 

Carbon. 

Hydro- 
gen. 

Oxygen.  Azote. 

SalU 

and 

earths. 

1st 
2d&3d 

Dung^^  fallow.    . 

Straw 

Total 

Manure  employed 

Difference    .    .    . 

lbs. 

9041 

6875 

lbs. 

2600 
5080 

lbs. 
2462 

lbs. 

150 
270 

lbs. 

1128 
1979 

lbs. 

lbs. 

'62 

356 

S 

7680 
3795 

3413 
1358 

420 
159 

'S 

fS 

418 
1222 

8414 

3885 

2055 

261 

2128 

4 

804 

No.    5,    CONTINUOUS    POTATO   CROPS- 


! 
Yean.  1       Substances. 

Crops 
per  acre. 

Crops 
dry. 

Carbon. 

Hydro- 
gen. 

Oxygen. 

Azote. 

Salts 

and 

earths. 

l8t&2d 

Potatoes    .... 
Stalks       .... 

Total 

Manure  employed  . 

Difference     .    .    . 

S 

lbs. 

10289 

.1 

10289 

lbs. 
161 
90 

lbs. 
605 
630 

74323 
41663 

32580 
8624 

■S 

■1^ 

'^ 

251 
172 

1235 
2777 

23956 

11568        1438 

12430 

79 

1542 

No.  6,  QUATRENNIAIi   ROTATION,  ADOPTED   BY  M.  CRUD. 


Yean. 

Crops  grown. 

Crops 
per  acre. 

ELEMENTARY  INGREDIENTS  OF  THE  CROP. 

•ir 

Carbon. 

Hydro- 
gen. 

Oxygen. 

Azote, 

SulU 
earths. 

Ist 

2d&4th 

8d 

Hdlf  acre  of  ^tatoes 
Ditto  of  beet-rooU     . 
Wheat.  153  bushels   . 
Wheat-straw    .    ,    . 
Clover  three  cuttings 

Total 

Manure  consumed    . 

Difference    .... 

lbs. 
9167 

lbs, 

2847 
5243 
5793 

lbs. 
1312 

1 

290 

'1 

1235 
2190 

38 

if 

121 

1^ 

S 

8524 
2989 

991 
a30 

7422 
2154 

278 
167 

1110 
2688 

9980 

5535 

641 

6268 

111 

1578 

IN  CEOPS  AND  MANURE. 


859 


SUMMARY. 


1 

Dry  manure 

Dry  produce 

•5 

expendetl  upon 

Azote  con- 

obtained in 

Azote  con- 

ic maiterni 

Gain  in  aiote 

1 

one  acre  in 

tained  in  the 

one  year  upon 

tained  in  the 

one  year  upon 

\a  one  year 

one  year. 

manure. 

one  acre. 

produce. 

one  acre. 

upon  one  acre. 

1 

lbs. 

lbs. 

lbs. 

lbs. 

lbs. 

lbs. 

No.  1 

1862 

37 

3261 

46 

1996 

9 

No.  2 

1862 

37 

3204 

46 

1746 

9 

No.  3 

1862 

37 

3564 

54 

2513 

17 

No.  4 

1247 

23 

2567 

26 

1565 

3 

No.  5 

3710 

86 

16299 

125 

12758 

39 

No.  6 

2087 

42 

4582 

70 

2889 

. 

From  all  that  precedes,  it  is  obvious  that  rotations  which  include 
trefoils,  red  clover,  lucern,  and  sainfoin,  are  those  that  afford  con- 
siderably the  largest  proportion  of  organic  matter ;  a  fact,  indeed, 
which  if  not  legitimately  established,  has  still  been  long  acted  on 
in  that  system  of  cropping  which  embraces  forage  plants  as  an  ele- 
ment. Lucerns,  too,  when  they  have  taken  kindly,  yield  an  extra- 
ordinary quantity  of  forage,  as  every  one  may  see  by  turning  to  the 
produce  of  the  piece  under  that  crop  which  in  the  system  of  M.Crud 
succeeds  the  quatrennial  rotation.  At  the  end  of  his  rotation,  M.Crud 
always  lays  on  manure  in  the  ratio  of  18  tons  per  acre,  which  lasts 
for  six  years,  and  may  be  said  to  suffice  for  the  succession  of  crops 
in  the  appended  table  : 

Crops.  Produce  per  acre.  Contents  in  azote. 

Luceradry,           1st  year 3080  lbs.  72  lbs 

2dyear 9240  215 

3d  year   114.58  269 

"               4th  year 9240  213 

"               Sthyear 7333  172 

Wheat,                  6th  year 1448  28 

Straw 3645  11 

980 
Dang  employed 40233  205 

Total  gain  in  azote 775 

Gain  in  azote  per  annum  and  per  acre 130 

In  glancing  at  these  tables,  it  is  obvious  that  the  azote  of  the  crop 
always  exceeds  the  azote  of  the  manure.  Generally  speaking,  I 
admit  that  this  excess  of  azote  is  derived  from  the  atmosphere  :  but 
I  do  not  pretend  to  say  in  what  precise  manner  the  assimilation  takes 
place.  I  shall  only  quote  the  conclusion  of  a  paper  which  I  published 
on  the  subject  in  the  year  1837.*  Azote  may  enter  immediately  into 
the  constitution  of  vegetables,  provided  their  green  parts  have  the 
power  of  fixing  it ;  azote  may  also  enter  vegetables  dissolved  in  the 
water  which  bathes  their  roots,  and  which  always  contains  it  in  a 
certain  proportion.  Lastly,  it  is  possible  that  the  air  may  contain 
an  infinitely  minute  quantity  of  arnmoniacal  vapor,  as  some  natural 

•  Annales  de  Chimie,  t.  liix.  p.  366. 


360  BELATIONS   OF    ELEMENTS 

philosophers*  have  maintained,  and  that  this  assimilated,  decom- 
posed, and  recomposed  anew  by  the  plant,  is  the  source  of  its  azotized 
constituents. 

§  2.    OF    THE    RESIDUES    OF   DIFFERENT    CROPS. 

The  vegetable  matter  which  is  produced  in  the  course  of  a  season 
is  never  found  entirely  in  the  crop.  A  certain  quantity  of  it,  for 
instance,  always  remains  in  the  ground.  It  is,  therefore,  a  point  of 
interest  to  ascertain  what  quantity  of  elementary  matter  is  left  in  the 
soil  after  each  kind  of  crop  in  the  rotation  ;  precise  knowledge  of 
this  description  may  even  be  important  in  calculating  rotations,  for 
it  is  obvious  that  the  remains  of  the  crop  now  on  the  ground  must 
influence  that  which  is  to  follow,  and  in  the  course  of  a  rotation  the 
sum  of  the  residuary  matters  must  be  regarded  as  a  supplement  oi 
addition  to  the  manure  put  into  the  ground  at  its  commencement. 

In  the  systems  of  rotation  very  generally  followed  at  the  present 
time,  the  infloence  of  these  residuary  matters  is  manifest,  and  it  is 
partly  by  their  means  that  we  can  explain  how  a  quantity  of  manure, 
frequently  very  moderate,  should  suffice  for  the  whole  of  the  crops 
in  a  productive  rotation.  The  remarkable  effect  of  clover  has  not 
failed  to  arrest  attention  even  from  the  most  unobserving.  The 
wheat  crop  which  comes  after  our  drill  crop  in  Alsace,  beet  or 
potatoes,  averages  from  18  to  20  bushels  per  acre ;  but  the  wheat 
crop  that  succeeds  our  clover  averages  from  23  to  24  bushels  per 
acre. 

The  improvement  of  the  soil,  so  obvious  in  connection  with  clover, 
in  all  probability  also  occurs  in  connection  with  the  residues  of  other 
crops ;  but  as  in  most  instances  the  residue  merely  compensates  the 
loss,  or  lessens  its  extent,  the  effect  produced  is  less  remarkable, 
and  is  less,  indeed,  in  amount.  All  the  world  acknowledge,  then, 
that  the  residues  of  the  crops  that  enter  into  a  rotation  compensate 
in  greater  or  less  degree  for  what  is  carried  away  in  the  shape  of 
harvest,  and  that  in  some  cases  they  even  add  to  the  fertility  of  the 
soil ;  for  in  growing  crops  that  leave  a  large  quantity  of  residue,  it 
is  precisely  as  if  a  smaller  quantity  were  taken  from  a  given  extent 
of  surface.  But  what  is  the  amount  of  residue  or  refuse  which  is 
returned  to  the  soil  by  such  and  such  a  crop  ?  What,  in  a  word,  is 
the  value  of  this  residuary  matter  considered  as  manure  ?  This  is 
a  point  upon  which  only  the  most  vague  and  indefinite  ideas  are 
generally  entertained  ;  and  it  was  with  the  purpose  of  substituting 
positive  facts  for  mere  guesses,  that  I  determined  on  weighing  and 
analyzing  the  vegetable  residue  of  the  several  crops  that  enter  as 
elements  into  our  more  usual  rotations. 

My  experiments  were  made  upon  breadths  of  land  which  varied 
from  120  to  500  square  yards  in  extent.  The  clover  roots  and 
stubble  were  taken  up  with  the  spade,  and  before  being  dried,  were 
freed  from  adhering  earth  by  washing.  The  beet-leaves  and  pota- 
to-tops were  dried  at  once  in  the  oven  ;  and  it  was  from  each  of  the 

*  Saoisore  Recberches  Chimiques,  and  Liobig,  Agricultural  Chemistry. 


IN  CROPS  AND  MANURE.  36 

general  masses  reduced  to  powder  that  samples  were  taken  for  ulti- 
mate  analysis,  before  proceeding  to  which,  they  were  carefully  dried 
in  vacuo  at  230°  F. 

It  is  not  likely  that  any  accurate  mean  result  should  have  been 
come  to  from^  an  examination  of  the  produce  of  a  single  season.  I 
should  even  say  that  the  year  in  which  these  inquiries  were  under- 
taken was  little  favorable  to  them,  inasmuch  as  the  crops  were  gen- 
erally bad  ;  but  it  is  obvious  that  they  form  a  nucleus,  around  or  by 
the  side  of  which  the  results  of  other  seasons  may  be  arranged,  and 
an  average  from  larger  premises  come  to. 

POTATO    TOPS    OR   HAUM. 

A  piece  of  land  measuring  120  square  yards,  marked  off  from  a 
spot  that  had  suffered  from  drought,  yielded  47.0  lbs.  of  green  tops, 
which  were  reduced  by  drying  to  18.4  lbs.  A  similar  extent  of 
surface,  selected  from  a  part  of  the  field  that  looked  well,  gave  green 
tops  79  lbs.,  which  dried  in  the  air  were  reduced  to  16  lbs.  We 
should  thus  have  23^  cwts.  of  green,  and  6j  cwts.  of  dry  tops  per 
acre.  The  crop  of  potatoes  in  1839  yielded  at  the  rate  of  101^ 
cwts.  per  acre.  One  hundred  grammes,  or  3  oz.  4  dwts.  8  grs. 
troy,  of  the  top  dried  in  the  air,  lost  12  grammes,  or  7  dwts.  17  grs. 
by  thorough  drying  at  230°  F.  The  weight  of  the  tops  yielded  per 
acre,  taken  as  dry,  consequently  amounts  to  5  cwts.  2  qrs.  14  lbs., 
and  by  elementary  analysis  they  were  found  to  have  the  following 
composition : 

Carbon 44-8 

Hydrogen 5.1 

Oxygen 30.5 

Azote 2.3 

Salts  and  earths 17.8 

100.0 
LEAVES  OF  FIELD-BEET,  OR  MANGEL-WURZEL. 

Upon  a  surface  of  500  square  yards,  976  lbs.  of  leaves  were  gath- 
ered, the  weight  being  taken  two  days  after  the  roots  were  pulled  up. 

55  lbs.  of  leaves  reducible  to  powder  by  drying  in  an  oven,  were 
brought  to  6.6  lbs. 

3  oz.  4  dwts.  of  leaves  dried  and  pulverized,  lost  by  desiccation 
at  230"  F.  3|  dwts.  of  moisture.  The  6.6  lbs.  brought  to  that  state 
of  dryness  would  have  weighed  6.1  lbs.  With  these  data  it  is  found 
that  the  976  lbs.  of  green  leaves  gathered  upon  500  square  yards 
would  have  weighed  when  dry  108.9  lbs. ;  and  that  the  acre  produced 
85|  cwts.  of  green  and  9|  cwts,  of  dry  leaves.  The  crop  of  roots 
which  answers  to  that  quantity  of  leaves,  was  in  1839  but  6  tons,  2 
cwts.,  that  is  to  say,  little  more  than  half  a  crop  ;  for  our  average 
is  about  10|  tons. 

COMPOSITION  OF  DRY  LEAVES. 

Carbon 38.1 

Hydrogen 5.1 

Oxygen 30.8 

Azote 4.5 

Salts  and  earths 21.5 

100. 0 
31 


ORGANIC  ELEMENTS  :      MANl'  RES  AND  CRCPS. 


WHEAT    STUBBLE. 

From  120  square  yards  of  ground  we  have  obtained  13  lbs.  of 
Btubble  dried  in  the  air.  The  same  isurface  in  another  field  produced 
171  lbs. 

Thus  we  have  5|  cwts.  of  stubble  per  acre ;  but  as  wheat  recurs 
twice  in  the  rotation,  the  residues  must  be  doubled  ;  say,  IH  cwts. 
Stubble  loses  0.26  of  moisture  when  dried  completely  at  230°. 

In  1839,  the  wheat  after  the  drilled  crop,  or  £tfter  clover,  was  onlj 
17  bushels  per  acre.  

I  have  assigned  to  stubble  the  same  composition  as  that  of  straw. 

CLOVER    ROOTS. 

A  surface  of  120  square  yards  gave  44  lbs.  of  roots,  vveighed  after 
being  thoroughly  dried  in  the  sun  ;  when  pulverized  after  drying  in 
the  stove  the  weight  was  reduced  to  37  lbs. 

3  oz.  4  dwts.  of  powdered  roots  lost  by  drying,  at  a  temperature 
of  230°  F.,  5  dwts.  of  moisture.  Thus  the  44  lbs.  of  roots  dried  in 
the  sun  would  have  weighed  34  lbs.,  and  one  acre  would  have 
furnished  I2f  cwts.  of  residue  perfectly  dry. 

In  1839,  the  clover  crop  when  reduced  to  hay  was  far  below  the 
average. 

COMPOSITION    OF    THE    ROOTS. 

Carbon 434 

Hydrogen 5.3 

Oxygen 36.9 

Azote L8 

Salts  and  earth 12.6 


100.0 


OAT   STUBBLE. 


The  residue  of  the  oat  crop,  which  concludes  the  rotation  coarse, 
does  not  act  upon  the  present,  but  on  the  next  rotation  ;  in  the  same 
way  as  the  organic  remains  left  in  the  ground  by  the  oats  which  ter- 
minated the  antecedent  course,  exerted  their  influence  upon  the 
present  one.  In  1839,  the  oat  crop  was  above  the  average  ;  it  was 
as  high  as  16  cwts.  2  qrs.  18  lbs.  per  acre. 

One  French  are  of  the  land,  equal  to  120  square  yards  English, 
yielded  20  lbs.  of  stubble  dried  in  the  air,  or  at  the  rate  in  round 
numbers  of  8  cwts.  per  acre. 

In  the  following  table  I  have  given  a  srimmary  of  the  results  above 
stated,  combining  therewith  the  quantity  ind  the  comi>osition  of  the 
manure  expended  in  the  rotation. 


ORGANIC  ELEMENTS  OF  MANc^ES  AND  CROPS. 


363 


•UMMARY   OF  THE    FOREGOING   RESULTS. 


Nature  of 
the  crop. 

hat 
0^ 

II 

1^ 

Potatoes    . 
Beetroots  . 
Wheat  .  . 
Clover-hay 
Oats .... 

bs. 
11367 

s 

lbs. 
2739 

1^ 

1810 
1474 

9527 

Total  .  .  . 

31349 

Manure 
employed 

44995 

Nature  of  the 

residues  buried 

in  the  soil. 


Potatoetops  . 
Beetroot  leaves 
Stubble.  .  .  . 
Roots  dried  in 
the  sun  .  .  . 
Stubble  .... 


^1. 

1* 

Elementary  matter  of  the  residues. 

?^5 

is 
Is 

1 
1 

i 

>> 

s 

< 

^§1 

t 

lbs. 

.a 

950 

1418 

596 

460 

615 
•299 

r 

75 
32 

1^- 
1 

lbs. 
14 
48 
4 

1, 

lbs. 

67 

178 
30 

16182 

'4664 

2066 

244 

1643 

94 

617 

9314 

3335 

391 

2403 

186 

2995 

It  therefore  appears  that  the  refuse  or  residue  of  the  several  crops 
of  a  rotation  represent,  both  in  quantity  and  nature,  somewhat 
less  than  one  half  of  the  manure  originally  put  into  the  ground  ;  I 
say  somewhat  less,  because  it  must  be  remembered  that  in  the  sum 
of  these  residuary  matters,  the  beetroot  leaves  and  potato  tops  must 
not  be  allowed  to  stand  together,  the  one  crop  naturally  excluding 
the  other,  or  at  all  events  the  two  hoed  or  drilled  crops  not  entering 
in  this  proportion  into  the  same  rotation. 

The  large  quantity  of  organic  matter  restored  to  the  soil  by  several 
of  the  crops  in  the  series,  consequently  explains  how  the  rotation 
may  be  closed  without  its  being  found  indispensable  to  supply  any 
additional  manure  in  its  course.  It  seems  indubitable  that  without 
this  addition  of  elementary  matter,  the  fertility  of  the  soil  would 
decline  much  more  rapidly  than  it  does  ;  the  residue  of  each  crop  is 
nothing  more  than  a  portion  of  the  crop  itself  restored  to  the  ground  ; 
it  is  as  if  we  only  carried  off  one  portion,  the  larger  portion  of  the 
crop,  and  buried  another  portion  green. 

In  the  five  years'  rotation,  it  may  be  observed  that  there  are  two 
crops,  the  hoed  crop  and  the  forage  crop,  which  yield  substa^ices  to 
the  ground  that  are  both  abundant  in  quantity  and  rich  in  azotized 
matter,  and  it  is  unquestionable  that  these  crops  act  favorably  on  the 
cereals  which  succeed  them.  But  data  are  wanting  for  the  appre- 
ciation of  their  specific  utility  in  the  general  rotation.  We  see,  for 
instance,  that  despite  the  large  proportion  of  residuary  matter  left  by 
the  beet  or  mangel-wurzel,  this  plant  lessens  considerably  the  pro- 
duce of  the  wheat  crop  that  comes  after  it.  The  potato,  though  it 
leaves  much  less  refuse  than  the  beet,  seems  nevertheless  to  act  lesa 
unfavorably  than  this  vegetable.  Clover  leaves  more  residue  than 
the  potato,  and  on  this  ground,  alone,  ought  to  favor  the  cereal  that 
follows  it ;  but  it  has  a  favorable  influence  out  of  all  proportion  with 
its  quantity,  contrasting  this  with  the  residue  of  either  of  the  hoed 
crops  ;  a  fact  from  which  we  learn  that  the  visible  appreciable  influ- 
ence of  the  residuary  matters  of  preceding  crops,  upon  the  luxuriance 
of  succeeding  crops,  does  not  result  solely  from  their  mass,  even 
supposing  earh  to  be  possessed  of  equal  qualities  ;  this  other,  this 


364  INORGANIC  ELEMENTS  OF  MANURES  aN^  CBOPS. 

additional  effect,  depends  especially  on  an  influence  exerted  on  the 
Boil  by  the  crops  wiiich  leave  them.  Had  these  crops  been  power- 
fully exhausting,  we  should  expect  that  their  refuse  or  residue,  how- 
ever considerable  in  quantity,  could  do  no  more  than  lessen  the 
amount  of  exhaustion  produced  ;  in  which  case,  its  useful  influence, 
however  real,  would  pass  unnoticed,  were  it  estimated  by  the  produce 
of  the  succeeding  crop.  If,  on  the  contrary,  a  crop  has  been  but 
slightly  scourging,  whether  in  consequence  of  the  smallness  of  its 
quantity,  or  because  it  may  have  derived  from  the  air  the  major  part 
of  its  constituent  elements,  the  useful  influence  of  the  residue  will 
not  fail^to  be  conspicuous.  When  the  relative  value  of  different  sys- 
tems of  rotation  is  discussed  in  the  way  we  have  done,  we  in  fact 
estimate  the  value  of  the  elementary  matter  derived  from  the  atmo 
sphere  by  an  aggregate  of  crops ;  but  the  procedure  generally  fol- 
lowed is  silent  when  the  question  is  to  assign  to  each  crop  in 
particular  the  special  share  which  it  has  had  in  the  total  profit.  To 
reply  to  this  question,  of  which  a  knowledge  of  the  various  residues 
is  one  of  the  elements,  we  must  first  ascertain  the  quantity  of  ele- 
mentary matter  supplied  by  the  soil  and  the  atmosphere,  with  refer- 
ence to  each  of  the  crops  which  enter  into  the  rotation ;  in  other 
words,  the  same  investigations  must  be  undertaken  in  reference  to 
each  plant  considered  by  itself,  that  have  been  made  in  reference  to 
the  series  collectively.  There  is  unquestionable  room,  in  this  direc- 
tion, for  an  important  series  of  experiments. 

§  3.    OF    THE    INORGANIC    SUBSTANCES    OF    MANURES    AND    CROPS. 

We  have  but  just  considered  the  organic  matter  developed  in  a 
series  of  successive  harvests.  To  complete  the  study  of  rotations, 
to  the  extent  at  least  that  this  can  be  done  in  the  present  state  of 
science,  we  have  still  to  examine  the  relations  that  may  exist  between 
the  mineral  substances  which  enter  into  the  constitution  of  the  pro- 
duce, and  those  that  make  part  of  the  manure  given. 

We  have  already  shown  in  a  general  way  that  certain  mineral 
salts,  certain  saline  matters  or  salifiable  bases,  are  essential  to  the 
constitution  of  vegetables.  To  the  best  of  my  knowledge,  no  seed 
has  yet  been  met  with  that  is  without  a  phosphate  ;  and  it  is  now 
known  that  the  alkaline  salts  powerfully  promote  vegetation. 

Such  is  their  ascertained  influence,  indeed,  that  tobacco,  barley, 
and  buckwheat  sown  in  soils  absolutely  without  organic  matter,  but 
containing  saline  substances,  and  only  moistened  with  distilled  water, 
produced  perfect  plants,  which  flowered  and  fruited,  and  yielded  ripe 
seeds.*  Whence  it  follows,  that  the  presence  of  saline  matter  fa- 
vors remarkably  the  assimilation  of  the  azote  of  the  atmosphere 
during  the  act  of  vegetation. 

The  importance  of  considering  rotations  in  connection  with  the 
inorganic  substances  that  are  assimilated  by  plants  was  perfectly 
well  known  to  Davy.  "  The  exj  rtation  of  grain  from  a  country 
which  receives  nothing  in  exchange  that  can  be  turned  into  manure, 
must  exhaust  the  soil  in  the  long  run,"  says  the  illustrious  chemist  - 
•  Lieblg,  in  Journ.  de  Pharmacie,  vol.  Iv.,  3d  series,  p.  94. 


INORGANIC  ELEMENTS  OF  MANURES  AND  CROPS.  36ri 

who  ascribed  to  this  cause  the  present  sterility  of  various  parts  of 
Northern  Africa  and  of  Asia  Minor,  as  well  as  of  Sicily,  which  for 
a  long  succession  of  years  was  the  granary  of  Italy.  Rome  un- 
questionably contains  in  its  catacombs  quantities  of  phosphorus  from 
all  the  countries  of  the  earth. 

Professor  Liebig,  in  insisting  with  the  greatest  propriety  on  the 
useful  part  played  by  alkaline  bases  and  saline  matters  in  vegetation, 
has  shown  the  necessity  of  taking  inorganic  substances  into  serious 
consideration  in  discussing  rotations.  It  is  long  since  I  came  to  the 
same  conclusion  myself;  but  it  strikes  me,  that  to  be  truly  profitable, 
such  a  discussion  must  necessarily  rest  on  analyses  of  the  ashes  of 
plants  which  have  grown  in  the  same  soil,  and  been  manured  with 
the  same  dung,  the  contents  of  which  in  mineral  elements  were  al- 
ready known.  There  is  in  fact  a  kind  of  account  current  to  be  es- 
tablished between  the  inorganic  matter  of  the  crop  and  that  of  the 
manure.  Although  I  give  every  credit  to  the  fidelity  of  the  analyses 
of  vegetable  ashes  that  have  been  published  up  to  the  present  time, 
I  have  not  felt  myself  at  liberty  to  make  use  of  any  of  them  in  the 
direction  which  I  now  indicate.  I  have  not  thought  that  it  would  be 
fair  or  reasonable  to  contrast  such  heterogeneous  compounds,  as  the 
ashes  of  plants  grown  at  Geneva  and  Paris,  under  such  dissimilar 
circumstances,  with  those  of  vegetables  produced  on  a  farm  of  Al- 
sace, where  the  point  to  be  explained,  through  the  results  of  this 
contrast,  had  reference  to  a  particular  series  of  agricultural  phenom- 
ena. And  then  my  business  was  not  merely  with  the  scientific  ques- 
tion ;  the  manufacturing  or  commercial  element  in  the  consideration 
also  touched  me.  I  had  to  ascertain  how  I  was  likely  to  stand  at 
some  future  time,  did  I  presume  to  act  upon  the  conclusions  to  which 
I  came.  There  was  nothing  for  me  therefore  but  to  analyze  the 
ashes  of  the  several  vegetables  which  entered  as  elements  into  the 
rotation  followed  at  Bechelbronn,  but  confining  my  inquiries  to  that 
portion  of  the  vegetable  which  is  looked  upon  particularly  as  the 
crop,  so  much  of  the  plant  as  remains  on  the  ground  and  is  turned  in 
again,  of  course  taking  nothing  from  it. 

The  ashes  examined  were  almost  all  from  the  crops  of  1841,  two 
analyses  having  generally  been  made  of  each  substance  :  and  here 
I  ought  to  say,  that  in  this  long  and  tedious  labor,  in  which  I  spent 
Dearly  a  whole  year,  I  was  most  ably  seconded  by  Mr.  Letellier.  By 
way  of  preface,  I  should  say  that  in  these  analyses,  losses  will  fre- 
quently be  apparent,  which  for  the  most  part  exceed  the  limits  that 
in  the  present  day  are  tolerated  in  the  more  careful  operations  of  the 
laboratory.  These  deficiencies,  which  puzzled  me  a  good  deal  at 
first,  I  by  and  by  discovered  to  proceed  from  the  difficulty  of  incin- 
crating  certain  vegetable  substances  completely.  When  they  abound 
in  alkaline  salts,  they  leave  ashes  that  melt  so  readily,  that  it  becomes 
difl[icult  to  prevent  their  agglutination,  and  the  charcoal  that  is  not 
consumed  is  then  effectually  protected  against  any  further  action  of 
the  fire.  There  is  nothing  for  it  in  such  cases  but  to  incinerate  at 
the  lowest  temperature  possible,  and  then  a  little  moisture  is  apt  to 
be  left ;  the  charcoal,  however,  is  the  substance  that  occasions  th« 

31* 


866 


INORGANIC  ELEMENTS  OF  MANURES  .-.  ND  CROPS. 


main  difficulty,  and  the  more  important  loss.  To  quote  one  of  the 
instances,  that  of  wheat,  where  the  loss  or  deficiency  is  as  high  as 
24  per  cent.  I  may  say  that  a  direct  inquiry  after  charcoal  brought 
it  out  equal  to  2,  by  which  the  actual  deficiency  is  reduced  to  0.4. 
I  have  not,  however,  introduced  any  correction  for  carbon,  but  pre- 
sent the  reader  with  the  results  as  they  actually  presented  them- 
selves to  me.  Among  the  number  of  the  products  of  the  analyses, 
alumina  figures  beside  the  oxide  of  iron.  Alumina  is  an  earth  which 
I  have  always  met  with  in  minimum  quantity  in  the  ashes  of  plants, 
and  is  perhaps  accidental ;  it  may  proceed  from  the  earth  which  ad- 
heres to  all  herbaceous  plants,  and  from  which  it  is  so  difficult  to 
free  them  completely. 

COMPOSITION  OF  THE  ASHES  PROCEEDING  FROM  THE  PLANTS  GROWN 
AT  BECHELBRONN. 


Acids. 

V 

3 

11 

■5* 

Substances  which 

n 

. 

•z 

P 

V 

^ 

1 

g 

■~e 

m 

yielded  the  ashes. 

-i-- 

i?,^ 

« 

15 

ts 

53 

^■f 

"^•s 

^^ 

O 

^ 

g-i 

"e 

Potatoes    .... 

13.4 

7.1 i  11.3 

2.7 

1.8 

5.4 

51.5 

traces 

.•j.6 

0.5 

0.7 

Mangel-wurzel 
Turnips     .    . 

lfi.l 

1.6    6.1 

5.2 

7.0 

4.4 

:«.o 

6.0 

8.0 

2  5 

4.2 

14.0 

10.9    6.0 

2.9 

10.9 

4.3 

33.7 

4.1 

6.4 

1.2 

5.5 

Potato  tops    . 

11.0 

2-2  10.8 

1.6 

2.3 

1.8 

44.5 

truces 

13.0 

5.2 

7.6 

Wheat.    .    . 

(M) 

1.0 !  47.0 

traces 

2.9 

15.9 

iW.5 

traces 

1.3 

0  0 

2.4 

Wheat-straw 

0.() 

1.0 i    3.1 

0.6 

8,5 

5.0 

9,2 

0,3 

67.6 

1.0 

3.7 

Oats     .     .     . 

1.7 

1.0  14.9 

0.5 

3.7 

7.7 

12.9 

0.0 

5;i.3 

1.3 

3.0 

OaUstraw      . 

8.2 

4.11   3.0 

4.7 

8.3 

2.8 

24,5 

4.4 

40.0 

2.1 

2.9 

Clover      .     . 

2.5.0 

2.5     6.3 

2.6 

24.6 

6.3 

0.5 

5.3 

0.3 

0.0 

Peas     .     .     . 

0.5 

4.7   30.1 

1.1 

10.1 

11.9 

35  3 

2.5 

1.5 

traces 

2.3 

French  beans 

3.3 

1.3  26.8 

0.1 

5.8 

11.5 

4.9.1 

0.0 

1.0 

traces 

1.1 

Horse  beans  . 

1.0 

1.6  34.2 

0.7 

5.1 

8.6 

45.2 

0.0 

0.5 

traces 

3.1  1 

1 

If  these  analytical  results  be  now  applied  to  the  produce  of  an 
acre  of  ground,  we  should  have  the  precise  quantities  of  minera. 
substances  abstracted  from  the  soil  by  each  of  the  several  crops  tha 
enter  into  the  rotation.     Here  they  are  in  a  table  : 

MINERAL    SUBSTANCES    TAKEN    UP    FROM    THE    SOIL    BY    THE    VARIOUS 
CROPS    GROWN    AT    BECHELBRONN    UPON    ONE    ACRE, 


1 

i 

1 

< 

P 

Acids. 

1 

i 

1 

1 

1 

i 

0 

Crop. 

II 

11 

Ih^. 

Ih^ 

lbs. 

Ihs, 

IM 

IN. 

llw. 

lbs. 

lb.. 

lbs. 

lbs. 

Potatoes 

2828 

4.0 

113 

13 

8 

3 

2 

6  1    58 

6 

"a 

Beet-roots     .... 

2908 

6  3 

183 

11 

3 

9 

13 

81    82 

15 

Half  crop  of  turnips,  ) 

consumed  off  the> 

mi 

7.6 

50 

8 

5 

U 

2 

19 

3 

0.7 

ground,                   S 

Potato  tops  ....•' 

5042 

6,0 

303 

33 

7 

A 

m 

5J9 

16 

Wheat     .    . 

1052 

24 

25 

12 

0.3 

'  R 

7 

0.4 

, , 

WheatJtraw 

2,^58 

70 

179 

5 

1.5 

1 

1 

17 

121 

li 

Ojit-straw'    .' 

1^5 

40 

39 

6 

0.4 

0,2 

lii 

5 

21 

0.6 

1176 

5  1 

60 

u 

2.5 

3 

1-5 

17 

24 

1 

-AiKi 

77 

284 

18" 

7 

7 

70 

18 

77 

15 

0.9 

Manured  peas 

915 

31 

28 

8 

1.2 

0? 

3 

3 

10 

0.5 

traces. 

French  beans 

1448 

3,5 

51 

13 

0.7 

01 

3 

6 

2.i 

0.6 

traces. 

Horse  beans      .    .    . 

1944 

3.0 

58 

20 

0.75 

0.5 

3 

5 

^ 

0.3 

traces. 

INORGANIC  ELEMENTS  OF  MANURES  AND  CROPS.  367 

On  looking  at  this  table  we  perceive  that  a  medium  crop  of  wheat 
takes  from  one  acre  of  ground  about  12  lbs.,  and  a  crop  of  beans 
about  20  lbs.  of  phosphoric  acid  ;  a  crop  of  beet  takes  11  lbs.  of  the 
same  acid,  and  further,  a  very  large  quantity  of  potash  and  soda.  It 
is  obvious  that  such  a  process  tends  continually  to  exhaust  arable 
land  of  the  mineral  substances  useful  to  vegetation  which  it  con- 
tains ,  and  that  a  term  must  come  when,  without  supplies  of  such 
mineral  matters,  the  land  would  become  unproductive  from  their  ab 
straction.  In  bottoms  of  great  fertility,  such  as  those  that  are  brought 
under  tillage  amidst  the  virgin  forests  of  the  New  World  at  the  pres- 
ent day,  it  may  be  imagined  that  any  exhaustion  of  saline  matters 
will  remain  unperceived  for  a  long  succession  of  years  ;  for  a  sue 
cession  of  ages  almost.  And  in  South  America,  where  the  usual 
preliminary  to  cultivation  is  to  burn  the  forest  that  stands  on  the 
ground,  by  which  the  saline  and  earthy  constituents  of  millions  of 
cubic  feet  of  timber  are  added  to  the  quantities  that  were  already 
contained  in  the  soil,  I  have  already  had  occasion  to  speak  of  the 
ample  returns  which  the  husbandman  receives  for  very  small  pains.* 
Under  circumstances,  in  the  neighborhood  of  large  and  populous 
towns,  for  instance,  where  the  interest  of  the  farmer  and  market- 
gardener  is  to  send  the  largest  possible  quantity  of  produce  to  mar- 
ket, consuming  the  least  possible  quantity  on  the  spot,  the  want  of 
Baline  principles  in  the  soil  would  very  soon  be  felt,  were  it  not  that 
for  every  wagon-load  of  greens  and  carrots,  fruit  and  potatoes,  corn 
and  straw,  that  finds  its  way  into  the  city,  a  wagon-load  of  dung, 
containing  each  and  every  one  of  the  principles  locked  up  in  the 
several  crops,  is  returned  to  the  land,  and  proves  enough,  and  often 
more  than  enough,  to  replace  all  that  has  been  carried  away  from  it. 
The  same  principle  holds  good  in  regard  to  inorganic  matters,  which 
we  have  already  established  with  reference  to  organic  substances. 

The  most  interesting  case  for  consideration  is  that  of  an  isolated 
farming  establishment — a  rural  domain,  so  situated  that  it  can  obtain 
nothing  from  without,  but  exporting  a  certain  proportion  of  its  pro- 
duce every  year,  has  still  to  depend  on  itself  for  all  it  requires  in  the 
shape  of  manure.  I  have  already  shown,  with  sufficient  clearness, 
I  apprehend,  how  it  is  that  lands  in  cultivation  derive  from  the  at- 
mosphere the  azotized  principles  necessary  to  replace  the  azotized 
products  ff  the  farm,  which  are  continually  carried  away  in  the 
shape  of  grain,  cattle,  &c.  I  have  now  to  show  how  the  various 
saline  substances,  the  alkalies,  the  phosphates,  &c.,  which  are  also 
exported  incessantly,  are  replaced.  I  believe  that  I  shall  be  able, 
with  the  assistance  of  chemical  analysis,  to  throw  light  on  one  of 
the  most  interesting  points  in  the  nature  and  history  of  cropping,  and 
succeed  in  practically  illustrating  the  theory  of  rotations.  In  what 
is  to  follow  immediately,  I  shall  always  reason  on  the  practical  data 
collected  at  Bechelbronn,  and  which  have  already  served  for  the 

*  The  first  breaks  of  the  early  English  settlers  in  North  America  are  now  either  very 
Indifferent  soils,  or  they  have  only  been  restored  to  some  portion  of  their  original  fer- 
tility by  monarlng;  so  that  the  supply  of  fertilizing  eletoents  is  not  inexhaustible  — 
Exa  Eo 


868  INORGANIC  ELEMENTS  OF  MANXTRES  AND  CBOPS. 

illustration  of  other  particulars.  My  farm,  I  may  say,  by  way  of 
preliminary,  is  an  ordinary  establishment ;  the  lands  which  have 
been  brought  by  a  system  of  rational  treatment  to  a  very  satisfactory 
state  of  fertility,  are  not  rich  at  bottom  and  originally,  and  they  fall 
off  rapidly  if  they  have  not  the  dose  of  manure  at  regular  intervals, 
which  is  requisite  to  maintain  them  in  their  state  of  productiveness. 
My  first  business  was  to  determine  the  nature  and  the  quantity  of 
the  mineral  substances  contained  in  my  manure  ;  and  with  a  view  to 
arrive  at  this  information,  I  burned  considerable  quantities  of  dung 
at  different  periods  of  the  year,  mixed  the  ashes  of  the  several  in 
cinerations,  and  from  the  mixture  took  a  sample  for  ultimate  analysis 
The  mean  results  are  represented  by  : 

(Carbonic 2.0 

Acids  <  Phosphoric 3.0 

(Sulphuric 1.9 

Chlorine 0.6 

Silica,  sand 66.4 

Lime 8.6 

Magnesia 3.6 

Oxide  of  iron,  alumina 6.1 

Potash  and  soda 7.8 

100.0 

But  our  farm-yard  dung  is  not  the  only  article  we  are  in  the  habit 
of  giving  to  our  land  ;  it  further  receives  a  good  dose  of  peat-ashes 
and  gypsum.  I  here  recall  to  the  reader's  mind  that  the  mean  com- 
position of  peat-ashes  is  this  : 

Silica 65.5 

Alumina 16.2 

Lime 6.0 

Magnesia 0.6 

Oxide  of  iron 3.7 

Potash  and  soda 23 

Sulphuric  acid. 5.4 

Chlorine • 0.3 

100.0 

In  the  system  followed  at  Bechelbronn,  the  farm-yard  dung  laid 
upon  an  acre  contains  26  cwts.  3  qrs.  of  ashes.  On  our  clover  leas 
we  spread  the  first  year  7  cubic  feet  of  turf-ashes ;  and  in  the  begin- 
ning of  spring  of  the  second  year,  we  lay  on  as  much  more,  say  14 
cubic  feet,  in  all  weighing  about  2  tons.  I  do  not  take  the  8  cwts. 
of  gypsum  which,  in  conformity  with  usage,  the  second  year's  clover 
generally  receives,  because  I  believe  this  addition  to  be  perfectly 
useless  after  the  very  sufficient  dose  of  peat-ash  which  we  employ. 

The  whole  of  the  mineral  substances  given  to  the  land  in  the 
course  of  five  years  per  acre  is  as  follows,  viz.  :  Ashes  contained  in 
the  manure  and  in  the  peat-ashes,  7624  lbs. ;  consisting  of  phos- 
phoric acid  90  lbs.,  sulphuric  acid  304  lbs.,  chlorine  4.5  lbs.,  lime 
532.5  lbs.,  magnesia  135.6  lbs.,  potash  and  soda  339  lbs.,  silica  and 
sand  4630  lbs.,  oxide  of  iron,  &c.,  353  lbs. 

It  is  therefore  easy  to  perceive,  from  the  preceding  data,  that 
what  with  the  manure  and  the  ashes  it  receives,  the  land  is  more 
than  supplied  with  all  the  mineral  substances  required  by  the  sev- 
eral crops  it  produces  in  the  course  of  the  rotation.     Let  us  cast  a 


INORGANIC  ELEMENTS  0/  MANURES  AND  CROPS. 


369 


glance  over  these  with  reference  to  their  mineral  or  inorganic  con- 
stituents, as  we  have  already  done  in  so  far  as  the  organic  matters 
are  concerned  ;  let  us  compare,  in  a  word,  the  quantity  and  the  na- 
ture of  the  mineral  substances  removed  in  the  course  of  five  succes- 
sive years,  in  contrast  with  the  quantity  and  the  nature  of  the  same 
substances  supplied  at  the  commencement  of  the  series,  and  we  shall 
find  that  the  sums  of  the  phosphoric  acid,  sulphuric  acid,  and  chlo- 
rine, and  of  the  alkaline  and  earthy  bases  of  the  crops,  are  always 
smaller  than  the  quantities  of  the  same  substances  which  exist  in 
and  are  supplied  to  the  arable  soil. 

I  shall  institute  the  comparison  with  the  rotation  No.  1,  which 
begins  with  potatoes ;  and  further,  with  a  continuous  crop  which, 
as  the  one  that  is  most  common  and  convenient,  shall  be  Jerusalem 
artichokes.  I  have  not  thought  it  advisable  to  discuss  the  rotation 
No.  2,  in  which  beet  replaces  the  potato,  because  the  ashes  of  these 
two  crops  are  so  much  alike,  that  it  may  be  assumed  to  be  matter 
of  indifference  which  of  the  two  enters  as  the  drill-crop  element  into 
the  series.  With  reference  to  the  Jerusalem  artichoke,  I  shall  only 
remind  the  reader  that  the  piece  of  land  where  it  grows  receives  a 
dose  of  manure  every  two  years,  in  the  proportion  of  41245  lbs.  per 
acre,  which  manure  contains  2776  lbs.  of  mineral  constituent.  Fur- 
ther, in  the  course  of  each  winter  peat-ashes,  in  the  ratio  of  2700  lbs. 
per  acre,  are  laid  on  the  land  ;  and  that  the  stems  are  generally  in- 
cinerated on  the  spot,  and  the  ashes  they  contain  returned  directly 
to  the  soil. 

TABLE  OF  THE  MINERAL  MATTERS  OF  THE  CROPS  AND  MANURES  IN 
THE  COURSE  OF  A  ROTATION. 


Average  crop  per  acre. 

Mineral 

substances 

in  the 

crops. 

ACIDS. 

15 
O 

S 

.S 

fcC 

1 

i 

Phos- 
phoric 

Sul- 
phuric 

ROTATION  NO.  1. 

Potatoes ...••.... 

lbs. 

113 
.50 

358 

284 
39 
60 
50 

lbs. 
13 
24 
11 
18 
6 

I' 

lbs. 
8 

4 

7 

f 

lbs. 
3 

2 

7 

3 

1 

lbs. 

2 

1 

30 

,0 

5 
5 

lbs. 

6 

8 
18 
18 

3 

¥ 

lbs. 
58 
15 
34 
77 
5 
17 
19 

lbs. 
6 

242 
15 
20 
24 
3 

TM  ttn  •   iia  t-stra  w 

Sum  of  mineral  substances 

Mineral  substances  of  the  manure 

Excess  over  the  mineral  matters  of 

927 

7582 

'^ 

27 
304 

16 
32 

114 
533 

56 
136" 

225 
339 

310 
5049 

605 

14 
65 

277 
13 

15 
9 

417 
14 

79 
11 

114 
270 

4736 
79 

INCESSANT   PRODUCTION   OF  THE  JE- 
RUSALEM POTATO. 

Island  2d  years:   mineral  matters 

2777 
4583 

65 

53 

248 

17 
14 

239 
275 

100 

27 

219 
105 

1843 
3002 

TMtlft  nf  tiirf  n«>iAa    

Whole  mineral  matters  of  manures 
Difference  in  favor  of  the  manures 

83 

301 

31 

514 

127 

324 

4845 

18 

287 

20.5 

500 

117 

52 

4767 

870  INORGANIC  ELEMENTS    OF  MANURES  AND   CROPS. 

It  was  at  one  time  asserted,  that  in  order  to  ensure  to  a  crop  of 
wheat  the  necessary  quantity  of  phosphates,  its  cultivation  w^as  pre- 
ceded by  one  of  roots  or  tubers,  or  leguminous  plants,  which  were 
supposed  to  contain  a  much  less  proportion  of  these  salts.  By  ref- 
erence, however,  to  the  table  of  mineral  substances,  removed  from 
the  soil  by  different  crops,  the  absurdity  of  such  reasoning  becomes 
evident.  For  example,  beans  and  haricots  take  20  and  13.7  lbs.  of 
phosphoric  acid  from  every  acre  of  land ;  potatoes  and  beet-root 
from  the  same  surface  take  but  11  and  12.8  lbs.  of  that  acid,  exactly 
what  is  found  in  a  crop  of  wheat.  Trefoil  is  equally  rich  in  phos- 
phates with  the  sheaves  of  corn  which  have  gone  before  it,  and  this 
large  dose  of  phosphoric  acid  withdrawn  from  the  soil,  will  nowise 
diminish  the  amount  which  will  enter  into  the  wheat  that  will  by 
and  by  succeed  the  artificial  meadow.  It  may  be  readily  under- 
stood, that  if  the  ground  contains  more  than  the  quantity  of  mineral 
substances  necessary  for  the  total  series  of  crops  in  a  rotation,  it  is 
a  matter  of  indifi'erence  whether  the  crops  draw  upon  the  soil  in 
any  particular  order,  and  these  succeed  according  to  rules  generally 
adopted  for  quite  different  reasons.  It  suits  well,  for  instance,  to 
begin  a  rotation  with  a  drill  crop  sown  in  spring,  and  which,  conse- 
quently, follows  in  our  system  the  oats  which  closed  the  preceding 
rotation  ;  it  is  a  great  advantage  to  be  able  to  collect  and  cart  out 
the  manure  during  winter.  Besides,  the  order  is  quite  at  the  farm- 
er's discretion,  and  there  are  places  where,  from  particular  reasons, 
quite  another  course  is  pursued.  One  part  of  the  produce  returns, 
as  has  been  shown,  to  manure,  after  having  served  as  fodder  for  the 
animals  belonging  to  the  farm.  The  inorganic  matters  are  restored 
to  the  earth  from  which  they  came,  deducting  the  fraction  assimi- 
lated in  the  bodies  of  the  cattle.  Lastly,  the  whole  of  the  wheat, 
and  a  certain  amount  of  flesh  will  be  exported,  and  with  these  a  no- 
table quantity  of  inorganic  matter.  Thus,  in  the  above  described 
rotation  of  five  years,  the  minimum  exportation  of  saline  substances 
which  must  be  removed  from  every  acre  of  land,  may  be  represent- 
ed by  27|  lbs.  of  phosphoric  acid,  and  from  36  to  45  lbs.  of  alkali ; 
this  is  just  so  much  lost  for  the  manure,  and  as  there  is  definitively 
found  at  the  end  of  the  rotation  a  quantity  of  manure  equal  and 
nearly  similar  to  that  disposed  of  at  the  commencement,  it  is  essen- 
tial that  the  loss  of  mineral  substance  be  made  up  from  without, 
unless  it  be  naturally  contained  in  the  soil. 

In  my  first  researches  on  the  rotation  of  crops,*  I  stated  that 
wherever  there  are  exportable  products,  it  becomes  indispensable  to 
keep  a  large  proportion  of  meadow  land,  quoting,  as  an  extreme 
case,  the  triennial  rotation  with  manured  summer-fallow.  It  is,  in 
fact,  the  meadow  which  restores  to  the  arable  land  the  principles 
which  have  been  carried  off.  This  point,  advanced  upon  analogy, 
is  amply  confirmed  by  the  results  of  analysis. 

I  have  examined,  in  reference  to  this  question,  the  ashes  of  the 
hsLy  of  our  meadows  of  Durrenbach,  irrigated  by  the  Sauer.     The 

*  Memok  COTununkated  to  the  Acad^mie  des  Science^  in  1838 


INORGANIC  ELEMENTS  OF  MANURES  AND  CROPS.  371 

analyses  were  made  with  ashes  furnished  by  the  crops  of  1841  and 
1842. 

I.  II.  III.  Average 

(Carbonic 9.0  5.5  "  7  3 

Acids      <  Phosphoric    5.3  5.3  5.5  5.4 

(Sulphuric 2.4  2.9  "  2.7 

Chlorine 2.3  2.8  "  2.6 

Lime   20.4  15.4  "  17.9 

Magnesia 6.0  8.3  "  7.2 

Potash 16.1  27.3            "  21.7 

Soda 1.2  2.3  "  1.8 

Silica 33.7  29.2  "  31.5 

Oxide  of  iron,  &c 1.5  0.6  0.5  0.9 

Loss 2.1  0.4  "  1.0 

100.0  100.0  100.0 

No.  1  yielded  6.0  per  cent,  of  ash. 

No.  2      "       6.2     idem. 

In  admitting  as  the  average  yearly  return  of  our  irrigated  mead- 
ows, 3666  lbs.  of  hay  and  after-grass  for  the  acre,  it  appears  that 
we  obtain,  from  a  corresponding  surface  of  land,  223.6  lbs.  of  ash, 
containing : 

(Carbonic 16.3 

Acids     <  Phosphoric 12.1 

(Sulphuric    6.0 

Chlorine  5.7 

Lime 39.1 

Magnesia 16.1 

Potash  and  soda 52.0 

Silica 70.4 

Oxide  of  iron,  andloss:. 4.2 

221.9* 

In  reckoning,  as  I  have  done,  the  lowest  annual  exportation  of 
mineral  substance  from  one  acre  of  arable  land  at  5.5  lbs.  of  phos- 
phoric acid  and  8.2  lbs.  of  alkali,  (potash  and  soda,)  there  must,  in 
order  to  make  up  for  loss,  arrive  each  year  at  the  farm  a  quantity 
of  hay  corresponding  to  about  1800  lbs.  for  every  acre  of  ploughed 
land,  which  would  establish  between  the  arable  and  meadow  land,  a 
relation  somewhat  less  than  1  to  ^. 

In  practice,  the  relation  in  question  is  sensibly  less  than  that  de- 
duced from  analysis  ;  in  some  farms  the  meadow-land  only  occupies 
a  fourth  or  fifth  of  the  whole  surface.  When  rye  replaces  wheat, 
the  extent  in  meadow-land  may  be  still  more  limited.  It  deserves 
notice,  that  I  have  supposed  the  arable  land  as  destitute  of  proper 
inorganic  matter,  and  that  all  came  from  the  manure  ashes  and  lime 
laid  on,  which  is  not  rigorously  true.  Tnere  are  soils  containing 
traces  of  phosphates,  and  it  is  difficult  to  find  clay  or  marl  exempt 
from  potash.  Nevertheless,  many  clear-headed  practical  men  begin 
to  suspect  that  meadow  has  been  too  much  sacrificed  to  arable  land. 
In  localities  placed  in  similar  conditions  to  those  in  which  we  are, 
removed  from  every  source  of  organic  manures,  which,  as  I  have 
shown  in  concert  with  M.  Payen,  are  always  furnished  with  saline 

*  The  sura  Is  only  too  small  here  from  the  number  of  places  of  dedtnals  not  havli|| 
been  carried  out  far  enough. — Evo.  Ed. 


372  INORGANIC  ELEMENTS  OF  MANURES   AND  CROPS. 

principles,  an  attempt  has  been  made  to  imitate  what  is  done  in  more 
favored  districts,  where  it  is  possible,  for  example,  to  add  animal 
remains  to  the  manure.  The  corn  crops  felt  this  new  procedure  ; 
nor  could  it  be  otherwise.  But  now  there  is  a  reaction  in  the  op- 
posite sense,  and  I  could  name  most  thriving  establishments,  where 
one-half  of  the  farm  is  in  meadow.  The  ever-increasing  demand 
for  butcher-meat  will  further  this  movement  to  the  great  advantage 
of  the  soil.  In  consequence  of  our  peculiar  position  at  Bechelbronn, 
nearly  halt  3ur  land  is  meadow,  which  allows  of  a  large  exportation 
of  the  prodjce  of  the  arable  land.  In  applying  the  results  of  the 
preceding  analyses,  I  find  that  each  year,  provided  there  is  no  loss 
the  hay  ought  to  bring  at  least  : 

1254  lbs.  of  phosphoric  acid, 


627 
602 

« 
it 

sulphuric  acid, 
chlorine, 

4155 

u 

lime, 

1672 
5456 
7312 

magnesia, 
potash  and  soda, 
silica. 

This  large  amount  of  mineral  substances  is  supplied  by  the  mead- 
ows, which  have  no  other  manure  than  the  water  and  mud  thereby 
deposited,  after  flowing  over  the  Vosges'  freestone  ;  they  receive 
no  manure  from  the  farm,  but  are  merely  earthed  with  the  sludge 
and  mire  borne  down  by  the  stream  ;  these  are  real  sources  of  saline 
impregnation.  Meadows  without  running  water  ought  not  to  be 
ranged  in  the  same  category,  they  only  give  the  principles  naturally 
contained  in  them  ;  hence,  they  must  be  always  manured  ev^ry 
three  or  four  years,  and  indeed,  if  not  situate  upon  a  naturally  rich 
soil,  are,  according  to  my  experience,  very  far  from  profitable. 

The  excess  of  mineral  matters  introduced  into  the  ground  over 
those  that  issue  with  the  crops,  an  excess  that  ought  always  to  be 
secured  by  judicious  management,  enriches  the  soil  in  saline  and 
alkaline  principles,  which  accumulate  in  the  lapse  of  years,  just  as 
vegetable  remains  and  azotized  organic  principles  accumulate  un- 
der a  good  system  of  rotation.  By  this,  even  in  localities  the  most 
disadvantageously  situate  for  the  purchase  of  manure,  temporary 
recurrence  may  be  had  to  the  introduction  of  such  crops  as  flax, 
rape,  &c.,  which  being  almost  wholly  exported,  leave  little  organic 
residuum  in  the  earth,  and  at  the  same  time  carry  oflf  a  considerable 
quantity  of  mineral  substance  ;  circumstances  which  determine,  as 
may  be  easily  conceived,  the  maximum  of  exhaustion,  and  for  that 
reason  wend  to  reduce  a  soil  becoming  over-rich  to  what  may  be 
called  the  standard  fertility. 

In  reviewing  the  chief  points  examined  it  will  be  seen,  that  as  far 
as  regards  organic  matter,  the  systems  of  culture  which  in  borrow- 
ing most  from  the  atmosphere,  leave  the  most  abundant  residues  in 
the  land,  are  those  that  constitute  the  most  productive  rotations.  In 
respect  to  inorganic  matter,  the  rotation,  to  be  advantageous,  to  have 
an  enduring  success,  ought  to  be  so  munaged  that  the  crops  ex- 


INORGANIC  ELEMENTS  OF  MANURES  AND  CROPS.  373 

ported  should  not  leave  the  dung-hill  with  less  than  that  constant 
quantity  of  mineral  substance  which  it  ought  to  contain.  A  crop 
which  abstracts  from  the  ground  a  notable  proportion  of  one  of  its 
mineral  elements,  should  not  be  repeatedly  introduced  in  the  course 
of  a  rotation,  which  depends  on  a  given  dose  of  manure,  unless  by 
the  effect  of  time  mineral  element  has  been  accumulated  in  the  land. 
A  clover  crop  takes  up,  for  example,  77  lbs.  of  alkali  per  acre.  If 
the  fodder  is  consumed  on  the  spot,  the  greater  portion  of  the  potash 
and  soda  will  return  to  the  manure  after  passing  through  the  cattle, 
and  the  land  eventually  recover  nearly  the  whole  of  the  alkali.  It 
will  be  quite  otherwise  if  the  fodder  is  taken  to  market ;  and  it  is  to 
these  repeated  exportations  of  the  produce  of  artificial  meadows 
that  the  failure  of  trefoil,  now  observed  in  soils  which  have  long 
yielded  abundantly,  is  undoubtedly  due.  Accordingly,  a  means  has 
been  proposed  of  restoring  to  these  lands  their  reproductive  power, 
by  applying  alkaline  manure.*  If  under  such  circumstances  carbo- 
nate of  soda  would  act  as  favorably  as  carbonate  of  potash  or  wood- 
ashes,  the  soda  salt,  in  spite  of  its  commercial  value,  might  prove 
serviceable,  and  deserves  a  trial. 

The  lime  manures  naturally  promote  the  growth  of  plants  of 
which  calcareous  salts  form  a  constituent ;  but  here  a  capital  distinc- 
tion must  be  made.  A  soil  may  contain  from  15  to  20  in  the  100  of 
lime,  and  still  be  unable  to  dispense  with  calcareous  manure ;  be- 
cause the  lime  is  in  some  other  state  than  as  it  exists  in  chalk,  as 
in  the  rubbish  of  pyroxene,  mica,  serpentine,  and  the  like.  A  soil 
of  this  kind,  although  replete  with  lime,  might  still  require  gypsum 
for  artificial  meadow,  and  chalk  for  wheat  and  oats.  It  is  from  the 
carbonate  that  plants  of  rapid  growth  derive  the  lime  essential  to 
them,  as  was  established  by  the  researches  of  Rigaud  de  Lille,  re- 
searches which  have  been  censured  by  agricultural  writers  to  whom 
they  were  unintelligible.  I  advocate  the  opinion  of  Rigaud,  be- 
cause in  the  Andes  of  Riobamba  I  have  seen  lucern  growing  in  au- 
gitic  rubbish,  very  rich  in  calcareous  matter,  and  yet  greatly  bene- 
fited by  liming. 

The  operation  of  gypsum  is  to  introduce  calcareous  matter  into 
plants.  This  I  have  endeavored  to  demonstrate  from  the  analysis 
of  the  ash  on  the  one  hand,  and  on  the  other,  from  the  consideration 
that  finely  divided  carbonate  of  lime,  as  it  exists  in  wood-ashes,  acts 
with  equal  efficacy  upon  artificial  meadows.  By  what  means  gyp- 
sum, if  it  does  not  enter  the  vegetable  as  a  sulphate,  parts  with  its 
sulphuric  acid,  is  at  present  conjectural.  It  appears  highly  proba- 
ble that  calcareous  matter  is  chiefly  beneficial  from  the  particular 
action  it  exercises  on  the  fixed  ammoniacal  salts  of  the  manure, 
transforming  these  successively,  slowly,  and  as  they  may  be  wanted, 
into  carbonate  of  ammonia.  In  the  most  favorable  condition,  the 
earth  is  only  moist,  not  soaked  with  water,  but  permeable  to  the  air. 
New  researches  will  perhaps  illustrate  the  utility  of  ammoniacal  va- 
pors thus  developed  in  a  confined  atmosphere,  where  the  roots  are 

*  Infiarmation  communicated  by  M.  Schattenmaim, 
32 


374  INORGANIC  ELEMENTS  OF  MANURES  AND  CROPS, 

in  operation.  At  least,  it  would  be  difficult  to  assign  any  other  office 
to  chalk  in  the  marling  or  liming  of  land  intended  for  corn,  when 
we  know  how  little  lime  corn  absorbs.  If,  indeed,  gypsum  promotes 
the  vegetation  of  trefoil,  lucerne,  sainfoin,  &c.,  by  furnishing  the 
needful  calcareous  element,  it  could  not  fail  to  exercise  an  equally 
farorable  agency  upon  wheat  and  oats,  did  they  require  it.  The  ex- 
periments adduced  prove  it  not  to  be  so,  and  their  results  are  in 
some  measure  corroborated  by  analysis.  Thus,  if  we  compare  the 
different  quantities  of  lime  withdrawn  from  the  soil  by  trefoil  arvd 
corn,  we  find  them  as  follows  : 

The  clover  crop  takes  from  1  acre  of  ground  nearly  70  lbs.  of  Ume. 
Wheat  "  "  "  16 

Oat       ^  "  "  "  6.4       " 

With  this  comparison  before  us,  it  seems  evident  that  if  the  marl- 
ing and  liming  of  corn  lands  had  no  other  object  than  the  introduc- 
tion of  the  minute  portion  of  lime  which  is  encountered  in  the  crops, 
it  would  be  difficult  to  justify  the  enormous  expenditure  of  calcare- 
ous carbonate  which  is  proved  by  daily  experience  to  be  advan- 
tageous. 

It  may  be  inferred  from  the  foregoing,  that  in  the  most  frequent 
case,  namely,  that  of  arable  lands  not  sufficiently  rich  to  do  without 
manure,  there  can  be  no  continuous  cultivation  without  annexation 
of  meadow ;  in  a  word,  one  part  of  the  farm  must  yield  crops  with- 
out consuming  manure,  so  as  to  replace  the  alkaline  and  earthy  salts 
that  are  constantly  withdrawn  by  successive  harvests  from  another 
part.  Lands  enriched  by  rivers  alone  permit  of  a  total  and  contin- 
ued export  of  their  produce  without  exhaustion.  Such  are  the  fields 
fertilized  by  the  inundations  of  the  Nile  ;  and  it  is  difficult  to  form 
an  idea  of  the  prodigious  quantities  of  phosphoric  acid,  magnesia, 
and  potash,  which  in  a  succession  of  ages  have  passed  out  of  Egypt 
with  her  incessant  exports  of  corn. 

Irrigation  is,  without  doubt,  the  most  economical  and  efficient 
means  of  increasing  the  fertility  of  the  soil,  out  of  the  abundant  for- 
age which  it  produces,  and  the  resulting  manure.  Plants  take  up 
and  concentrate  in  their  organs  the  mineral  and  organic  elements 
contained  in  the  water,  sometimes  in  proportions  so  minute  as  to  es- 
cape analysis  ;  just  as  they  absorb  and  condense,  in  modified  forms, 
the  aeriform  principles  which  constitute  but  some  10,000th  parts  in 
the  composition  of  the  atmosphere.  It  is  thus  that  vegetables  col- 
lect and  organize  the  elements  which  are  dissolved  in  water,  and 
disseminated  through  the  earth  and  the  air,  as  a  preparative  to  their 
being  assimilated  by  animals. 


jRlGm   OF   ANIMAL   PRINCIPLES.  375 


CHAPTER  VIII. 

OF  THE  FEEDING  OF  THE  ANIMALS  BELONGING  TO  A  FARM; 
AND  OF  THE  IMMEDIATE  PRINCIPLES  OF  ANIMAL  ORIGIN. 

^  I.    ORIGIN    OF   ANIMAL    PRINCIPLES. 

It  is  now  generally  admitted  that  the  food  of  animals  must  ne- 
cessarily contain  azote  ;  and  this  circumstance  has  led  to  the  infer- 
ence, that  the  herbivorous  tribes  obtain  from  their  food  the  azote 
which  enters  into  the  constitution  of  their  bodies. 

In  a  general  way,  the  individual  consuming  a  certain  portion  of 
food  every  day,  nevertheless  does  not  increase  in  his  average 
weight.  This  is  what  occurs  with  animals  upon  the  quantity  of 
food  which  is  known  to  be  sufficient  for  their  keep  ;  and  it  has  been 
found  that  the  human  subject,  living  very  regularly,  returns  at  a  cer- 
tain hour,  or  at  certain  hours  of  the  day,  to  a  certain  mean  weight. 
Grooms,  farm  servants,  &c.,  are  perfectly  well  aware  of  the  fact, 
that  with  a  certain  allowance  of  hay  and  corn,  a  horse  will  be  kept 
in  the  condition  necessary  to  do  the  work  required  of  him  without 
either  gaining  or  losing  in  flesh. 

Under  such  circumstances,  the  whole  of  the  elementary  matter 
contained  in  the  food  consumed,  ought  to  be  found  in  the  dejections, 
the  excretions,  and  the  products  of  the  act  of  respiration.  And  as- 
suming that  this  is  so,  it  might  then  be  maintained  that  none  of  the 
elements  is  assimilated,  assimilation  being  taken  in  the  sense  of  an 
addition  of  principles  introduced  with  the  food  to  the  principles  al- 
ready present  in  the  body.  Yet  is  there  unquestionably  assimila- 
tion, in  the  sense  that  the  alimentary  matters  of  the  food  become 
fixed  in  the  system,  having  there  undergone  modification  or  change  ; 
and  that  they  replace,  or  come  instead  of  other  elements  of  the 
same  kind,  which  are  daily  thrown  oflf  by  the  vital  acts  of  the 
economy. 

During  the  nutrition  of  a  young  animal,  and  also  in  the  process 
of  fattening  an  adult,  things  go  on  differently  ;  here  there  is  unques- 
tionably definitive  fixation  of  a  portion  of  the  matter  contained  in  the 
food  :  there  is  no  longer  balance  between  the  waste  and  the  supply  ; 
an  animal  then  increases  in  weight  notably  and  rapidly. 

Looking  at  the  question  of  feeding  in  the  most  general  way,  then, 
I  admit  that  an  adult  animal,  upon  the  daily  allowance,  voids  a 
quantity  of  matter  in  its  various  excretions  precisely  equal  to  the 
quantity  which  it  receives  in  its  food  :*  all  the  elements,  the  sajnne 
in  nature  and  in  quantity,  which  are  contained  in  the  food,  are  also 
contained  in  the  excrements,  vapors,  and  gases,  which  pass  off  from 
the  living  body  ;  carbon  and  azote,  hydrogen  and  oxygen,  phospho- 

*  Boussinganlt,  Annales  de  Chimie,  3e  sirie,  t.  Ixzzi,  p.  IH 


376  ORIGIN    OF    ANIMAL    PRINCIPLES. 

rus,  sulphur,  and  chlorine,  calcium,  magnesium,  srdium,  potassium 
and  iron,  as  they  are  all  encountered  in  the  food  •  j  are  they  all  en 
countered  in  the  body,  and  also  in  the  excretions  cf  an  animal  ;  ana 
it  seems  certain,  that  no  one  of  these  primary  or  simple  substance* 
can  be  wanting  in  the  nutriment  without  the  body  very  speedilj 
feeling  the  ill  effects  of  its  absence.  Iron,  for  example,  is  a  con 
stant  principle  in  the  coloring  matter  of  the  blood  ;  it  also  exists  ii 
large  quantity  in  the  hair  ;  and  he  who  should  live  on  food  that  con 
tained  no  trace  of  it  would  certainly,  and  before  long,  become  disor 
dered  in  his  health. 

In  what  has  just  been  said,  I  take  it  for  granted  that  animals  dt 
not  absorb  or  assimilate  any  of  the  azote  which  forms  so  large  a 
constituent  in  the  air  they  breathe  ;  and  I  am  warranted  in  this  by 
the  researches  of  every  physiologist  of  any  name  or  distinction.  Not 
only  do  animals  obtain  no  azote  from  the  atmosphere,  but  they  actu- 
ally exhale  it  incessantly,  as  was  proved  by  M.  Despretz  in  the 
course  of  his  numerous  experiments,  and  as  I  myself  also  demon- 
strated in  the  inquiries  I  undertook  to  ascertain  whether  herbivorous 
animals  obtained  azote  from  the  air  or  not.  The  azote  exhaled,  it 
was  discovered,  proceeded  entirely  from  the  food  consumed  by  the 
animal ;  a  fact  which,  already  of  great  importance  in  a  physiologi- 
cal point  of  view  and  in  reference  to  general  physics,  bears  at  the 
same  time  so  immediately  upon  one  of  the  most  important  questions 
of  agriculture,  that  I  think  it  well  to  give  the  particulars  of  one  of 
the  procadures  by  which  it  has  been  established. 

The  experiments  in  this  case  were  performed  on  a  milch-cow 
and  a  full-grown  horse,  which  were  placed  in  stalls  so  contrived 
that  the  droppings  and  the  urine  could  be  collected  without  loss. 
Before  boing  made  the  subjects  of  experiment,  the  animals  were  bal- 
lasted or  fed  for  a  month  with  the  same  ration  that  was  furnished  to 
them  during  the  three  days  and  three  nights  which  they  passed  in 
the  experimental  stalls.  During  the  month,  the  weight  of  the  ani- 
mals did  not  vary  sensibly,  a  circumstance  which  happily  enables  us 
to  assume  that  neither  did  the  weight  vary  during  the  seventy-two 
hours  when  they  were  under  especial  observation. 

The  cow  was  foddered  with  after-math  hay  and  potatoes  ;  the 
horse  with  the  same  hay  and  oats.  The  quantities  of  forage  were 
accurately  weighed,  and  their  precise  degree  of  moistness  and  their 
composition  were  determined  from  average  samples.  The  water 
drunk  was  measured,  its  saline  and  earthy  constituents  having  been 
previously  ascertained.  The  excrementitious  matters  passed  were 
of  course  collected  with  the  greatest  care  ;  the  excrements,  the 
urine,  and  the  milk  were  weighed,  and  the  constitutiaji  of  the  whole 
estimated  from  elementary  analyses  of  average  specimens  of  each. 
The  results  of  the  two  experim*  Us  are  given  in  this  table  : 


ELEMENTS  OF  FOOD  AND  OF  EXCRETIONS. 


377 


FOOD    CONSUMED    BY    THE    HORSE    IN    24    HOURS.                         | 

Weight  in 
the  wet 
state. 

Weight   in 

Elememary  matter  in  the  food.                         1 

Forag^e. 

tlie  dry 
state. 

Carbon.    [Hydrogen. 

Oxygen,  j     Azote. 

S«lis  and 
enrihs. 

Water.       -       . 
Total,     .       . 

lbs. 

20 
6 
43 

lbs.  oz. 

lbs.  oz. 
7    11 
2     7 

Ib.oz.  dwt. 
0  10      7 
0    3    18 

lb.  oz.Uwi.  lb.  oz.dwt. 

6    8     8.03     2 
1  10    14  1  0    1      7 

b.  oz.dwt. 
1    6    14 
0    2    10 
0    0     8 

69 

23     6 

10     6    1  1    2     5 

8    7     2  1  0   4     9 

1    9   12 

PRODUCTS    VOIDED    BY    THE    HORSE    IN    24    HOURS. 

Producti. 

Weig-ht  in 
the  wet 
state. 

Weight  in 
the  dry 
state. 

Elementary  matter  in  the  producu.                     1 

Carbon. 

Hydrogen. 

Oxygen. 

Azote. 

Salts  and 
earths. 

Urine.        .      - 
Excrements,  - 

Total*  matter  of  ? 
the  food,      .     5 

Difference, 

lb.  oz.  dwt. 

lb.  oz.  dwt. 
0   9    14 
9    5     6 

lb  oz.dwt. 

§11? 

Ib.oz.  dwt. 
0    0     7 
0    5    15 

lb.  oz.  dwt. 
0    1      2 
3    6    14 

lb.oz.dw.. 
0    1      4 
0    2    10 

lb.  oz.  dwt. 

0  3    10 

1  6    10 

41    8    17 
69    0     0 

10   3     0 
22   6     0 

3  11     7 
10   6     0 

0  6     2 

1  2     5 

3    7    16 
8    7     2 

0    3    14 
0    4     9 

1  10     0 
1    9    12 

27    3     3  Il2   3     0 

6    6    13 

0    8     3 

4  11      6 

0    0    15 

0    0     8 

WATER    CONSUMED    BY    THE 
HORSE  IN  24  HOURS. 

WATER   VOIDED    BY  THE    HORSE 
IN    24    HOURS. 

With  the  hay,         .... 
With  the  oats,     .       .       -       . 
Taken  as  drink.      .... 

Total  eonsurned. 

lbs.  oz. 
2     3 

With  the  urine 

With  the  excrements. 

Total  voided, 

Water  consumed,        ... 

lbs.  oz. 

J  i 

38     4 

25    14 
38     4 

Water  exhaled  by  pulmonary  and  cutaneous  transpiration, 

12     6 

FOOD   CONSUMED   BY    THE   COW    IN    24    HOURS. 

Fodder 

Weight  in 
the  wet 
st&t«. 

Weight  in 
the  dry 
ttate. 

Elementary  matter  ot  the  food. 

Carbon. 

Hydrogen. 

Oxygen.  |     Azote. 

Salts  and 
earths. 

Potatoes,    .       . 
Atler-math  hay. 
Water,       .       . 

Total.     .       . 

lb.  oz.  dwt. 

^f  1 

160    0    0 

lb.  oz.  dwt. 
11    2     1 
16  11     0 

lb.  oz.  dwt. 
4  11     2 
7  11    11 

Ib.oz.  dwt. 
0    7    15 

on    7 

lb.  oz.  dwt.  lb.  02.  dwt. 

4  10    17  1  0    1    12 

5  10    17     0    4    17 

lb.  oz.  dwt. 

0  6    13 

1  8     6 
0    1    12 

220   3   7 

28    1     1 

12  10    13 

1    7     2 

10   9    14     0   6     9 

2   4    U 

PRODUCTS    VOIDED    BY    THE    COW    IN    24    HOURS. 

Product*. 

Weight  in 
the  wet 
slate. 

Weight  in 
the  dry 
state. 

Elementary  matter  in  the  producU. 

Carbon. 

Hydrogen. 

Oxygen. 

Azote. 

Salts  and 
earths. 

Excrements,  . 
Urine,        .       . 
Milk.       .       . 

Total, 
"  matter  of  food. 

Difference. 

lb.  oz.  dwt. 
76    1    9 

21  11  12 

22  10  10 

lb.  oz.  dwt. 
3    1     0 

lb.  oz.dwt. 
4    7     0 

0  8     7 

1  8     3 

lb.  oz.dwt. 

roil 

0    3     3 

lb.  oz.dwt. 

tl  1 

0  10     6 

lb.  oz.  dwt. 

lif'l 

0    1     9 

lb.  oz.  dwt. 
0    1    16 

120  11  11 

220   3    7 

16    4     9 
28    1     1 

6  11    10 
12  10    13 

0  10    12 

1  7     2 

5    6    18 
10   9    14 

0    5    11 
0   6     9 

2    5    10 
2   4    11 

99    3  16 

11    8   12 

5  11     3 

0   8   10 

5   2    16 

0   0    18 

0   0   19 

WATER   CONSUMED    BY  THE    COW 
IN  24  HOURS. 

WATER    VOIDED    BY  THE    COW    IN 
24    HOURS. 

With  the  potatoes. 

With  the  hay,     .... 

Taken  as  drink.      .       .       .       • 

T**a1  consumed. 

lbs.  oz. 

I'l 

132     0 

With  the  potatoes. 

With  the  urine 

With  the  milk.       ... 

Total  voided 

Water  consume'',   .... 

lbs.  oz. 
53    10 

15  14 

16  3 

158     5 

.i'l 

Water  passed  off 

ay  pulmon 

Etry  and 

eu 

taneou 

stre 

nspiration 

»     - 

. 

_raj!9 

378  COMBUSTION    OF    CARBON. 

From  these  f?ams  it  appears  that  the  azote  of  the  excrements  is 
less  by  from  339.6  to  455.0  grains  than  that  of  the  forage  consumed. 
It  appears  also  that  the  whole  q.  antity  of  elementary  matter  con- 
tained in  the  excrements  is  less  than  that  which  had  been  taken  as 
food ;  the  difference  is  of  course  due  to  the  quantities  which  were 
lost  by  respiration  and  the  cutaneous  exhalation. 

The  oxygen  and  hydrogen  that  are  not  accounted  for  in  the  sum 
of  the  products  have  not  disappeared  in  the  precist  proportions  re- 
quisite to  form  water ;  the  excess  of  hydrogen  amounts  to  as  many 
as  from  13  to  15  dwts.  It  is  probable  that  this  hydrogen  of  the 
food  became  changed  into  water  by  combining  during  respiration 
with  the  oxygen  of  the  air. 

The  loss  of  carbon,  which  is  very  considerable,  seeing  that  in  the 
two  experiments  it  aBiounts  to  nearly  12^  lbs.,  must  have  gone  to 
form  the  carbonic  acid,  which  is  known  to  be  so  large  and  import- 
ant a  constituent  in  the  expired  air,  and  which  is  also  exhaled  from 
the  general  surface  of  the  body.  Neglecting  the  latter,  it  appears 
that  each  of  the  animals  produced  in  the  course  of  twenty-four 
hours  upwards  of  13  cubic  feet  of  carbonic  acid  gas,  the  thermome- 
ter supposed  at  32*^  F.,  the  barometer  at  30  inches.* 

During  respiration,  then,  or  as  a  consequence  of  respiration,  the 
carbon  and  hydrogen  of  the  food  have  disappeared  and  given  rise, 
by  the  concurrence  of  the  oxygen  of  the  air,  to  carbonic  acid  and 
water,  precisely  as  if  they  had  been  burned.  And  an  animal  may, 
in  fact,  be  regarded  as  an  apparatus  or  system,  in  which  a  slow  com- 
bustion is  incessantly  going  on  ;  there  is  perpetual  disengagement 
of  carbonic  acid  gas  and  of  the  vapor  of  water,  just  as  there  is  from 
a  stove  in  which  any  organic  substance,  wood,  for  example,  is  burn- 
ing. In  either  case  there  is  evolution  of  heat ;  all  animals  have  a 
temperature  above  that  of  the  medium  which  surrounds  them,  and 
the  excess  of  the  elevation  is  in  some  sort  relative  to  the  activity  of 
the  respiratory  process,  or,  in  other  words,  to  the  intensity  of  the 
combustion. 

Under  the  influence  of  the  oxygen  that  is  taken  into  the  body,  the 
soluble  principles  of  the  blood  pass  through  a  series  of  modifications, 
the  last  of  which  is  carbonic  acid,  which  is  exhaled  and  dissipated 
in  the  air ;  and  it  is  in  this  way  that  a  portion  of  the  carbon  of  the 
food  is  returned  to  the  atmosphere,  after  having  accomplished  the 
important  function  of  supplying  the  animal  with  the  heat  that  is  ne- 
cessary to  its  existence.  Far  from  deriving  any  thing  from  the  air, 
consequently,  animals,  on  the  contrary,  are  continually  pouring  car- 
bon into  it.  The  food  is,  therefore,  the  only  source  whence  animals 
derive  the  matter  that  enters  into  their  constitution  ;  and,  as  tho 
primary  food  of  animals  is  obtained  from  vegetables,  herbivorous 
creatures  must  necessarily  find  in  the  plants  they  consume  all  the 

♦  The  large  quantity  of  carbonic  acid  shows  the  necessity  for  large  and  well-venti- 
lated stables  and  cow-houses.  A  cow,  i*  appears,  will  vitiate  66  cubic  feet  of  air  in 
a  day.  It  will  bs  observed  in  the  table  tliat  the  saline  and  earthy  matters  of  th« 
ejects  exceed  those  of  the  ingesta  in  both  instances.  This  is  from  error  in  observa 
tlon,  and  is  owing  to  the  difficulty  of  d  Uermining  exactly  the  quantities  of  these  sab 
ftaaces.    The  error  is  less  in  the  case  vf  the  hon*  than  in  that  of  the  cow. 


IDENTITY  OF  ANIMAL  AND  VEGETABLE  PRINCIPLES. 


370 


elements  they  assimilate.  It  might  be  expected  from  this,  that  the 
material  constitution  of  animals  should  approach,  and  sometimes  even 
be  identical  with  that  of  vegetables ;  and  it  is  found,  in  fact,  that  a 
considerable  number  of  ternary  or  quarternary  organic  compounds, 
of  either  kingdom,  present  the  greatest  analogy  to  one  another ;  their 
identity,  in  some  cases,  is  even  complete.  Some  fatty  substances 
of  animal  origin  do  not  differ  in  any  way  from  vegetable  fats ;  the 
margaric  acid  which  is  obtained  from  hog's  lard  has  the  precise 
characters  of  the  margaric  acid  which  is  furnished  by  olive  oil,  and 
the  same  identity  is  preserved  through  the  entire  series  of  quarter- 
nary azotized  principles,  as  a  glance  at  the  following  table,  which 
contains  the  results  of  the  analyses  performed  by  Messrs  Dumas 
and  Cahours,  will  show. 


MBRINK. 

ALBUMEN. 

CASEINS. 

Animal. 

Vegetable. 

Animal. 

Vegetable. 

Animal 

Vegetable. 

r   h 

52.8 

7.0 

23.7 

16.5 

53.2 

7.0 

23.4 

16.4 

53.5 

7.1 

23.6 

15.8 

53.7 

7.1 

23.5 

15.7 

53.5 

7.0 
23.7 
15.8 

53.5 

7.1 

23.4 

16.0 

Hydrogen 

100.0 

100.0 

100.0 

100.0 

100.0 

100.0 

These  principles,  to  which  must  be  added  gelatine,  the  fats  and 
several  earthy  and  alkaline  salts,  constitute  the  frame-work  of  the 
animal  tissues,  or  the  fluids  which  penetrate  them  ;  it  is  therefore 
necessary  for  us  to  examine  each  of  them  shortly. 

Gelatine  is  met  with  in  almost  all  the  solid  parts,  in  the  bones, 
tendons,  cartilages,  skin,  cellular  tissue,  muscular  flesh — all  contain 
it.  It  is  readily  soluble  in  boiling  water  ;  cold  water  only  takes  up 
a  small  quantity  of  it.  Two  or  three  parts  of  gelatine  dissolved  in 
100  parts  of  hot  water,  suffice  to  turn  the  fluid  into  a  tremulous  jelly 
when  it  has  become  cold.  Tannin,  or  infusion  of  gall-nuts,  precipi- 
tates gelatine  completely  from  its  solution,  the  precipitate  being  very 
bulky  and  perfectly  insoluble  in  water ;  and  it  is  this  chemical  com- 
bina  bn  or  principle  which  lies  at  the  bottom  of  the  art  of  tanning. 

Gelatine  is  extensively  used  in  the  arts,  under  the  familiar  name 

of  glue.     Isinglass  consists  of  gelatine  nearly  pure,  and,  according 

to  Mulder,  contains  : 

Carbon. 50.8 

Hydrogen 6.6 

Azote 18.3 

Oxygen 24J 

100.0 

Fihrine  occurs  in  a  state  of  solution  in  the  blood,  and  forms  the 
principal  ingredient  in  muscular  flesh.  It  is  readily  obtained  by 
whipping  a  quantity  of  blood  just  taken  from  the  veins  of  a  living 
animal ;  the  white  stringy  masses  that  adhere  to  the  rod  are  fibrine, 
which,  by  gentle  kneading  under  water,  become  colorless.    Fibrine, 


380  ALBUMEN,    CASEUM. 

when  moist,  is  a  highly  elastic  and  flexible  substance  ;  dried,  it  loses 
about  30  per  cent,  of  water,  and  becomes  brittle,  horny,  semi-trans- 
parent. Thrown  into  water,  it  gradually  imbibes  all  it  had  lost  by 
drying,  and  regains  its  former  properties.  Burned  and  incinerated, 
fibrine  leaves  a  quantity  of  ash,  which  consists,  for  the  major  part, 
of  phosphate  of  lime,  with  which  is  mixed  a  small  quantity  of  phos- 
phate of  magnesia  and  of  oxide  of  iron. 

Albumen  exists  in  large  quantity  dissolved  in  the  water  or  serum 
of  the  blood,  and  in  the  white  of  the  egg ;  it  is  also  found  in  almost 
all  the  animal  fluids  that  are  not  excretions,  or  destined  to  be  thrown 
oflf  as  useless  to  the  system.  Albumen,  as  familiarly  known,  has 
the  remarkable  property  of  coagulating  or  setting  into  a  soft  fluid,  at 
a  certain  temperature — 158°  F. 

Caseum,  or  caseine,  is  the  distinguishing  principle  of  milk.  By 
combining  vvith  acids  it  forms  an  insoluble  compound  ;  and  it  under- 
goes a  remarkable  coagulation,  as  all  the  world  knows,  in  contact 
with  a  piece  of  the  inner  membrane  of  the  stomach  of  a  young  ani- 
mal :  from  a  fluid  it  sets  into  a  soft  solid,  which  by  degrees  separates 
into  two  portions — whey  and  curd.  The  curd,  or  caseum,  always 
contains  fat,  and,  when  burned,  leaves  a  considerable  quantity  of 
ash. 

Physiologists  distinguish  three  principal  tissues  in  the  bodies  of 
animals ;  the  muscular,  the  nervous,  and  the  cellular. 

The  muscular  tissue  consists  of  an  assemblage  of  contractile  fibres, 
here  disseminated  through  the  masses  of  organs,  there  collected  into 
bundles  and  constituting  the  flesh.  This  is  the  instrument  by  which 
animals  perform  all  their  voluntary  motions,  and  it  is  that  also  by 
which  all  the  active  but  involuntary  movements  of  the  body  are  ex- 
cited. Muscular  flesh  is  always  a  compound  substance,  however ;  it 
consists  of  fibrine,  the  contractile  or  proper  element,  albumen,  fat, 
gelatine,  an  odorous  extractive  matter,  lactic  acid,  different  salts  and 
the  coloring  principle  of  the  blood. 

Put  into  cold  water,  so  long  as  the  temperature  is  below  from  130° 
to  140°  F.,  little  effect  is  produced  beyond  the  solution  of  the  soluble 
salts  which  it  may  contain,  and  of  a  portion  of  its  extractive  matter 
and  albumen.  At  from  175°  to  195°,  the  albumen  which  had  been 
dissolved,  coagulates  and  rises  to  the  top  as  scum,  and  the  fat  melts 
and  floats  on  the  surface.  The  fibrinous  element  of  the  meat,  how- 
ever, preserves  its  characters  even  after  the  action  of  boiling  water 
continued  for  some  time. 

The  nervous  tissue  constitutes  the  brain,  spinal  marrow,  and 
nerves,  distributed  to  all  parts  of  the  body.  Brain  in  its  composition 
contains  a  large  quantity  of  water, — 80  per  cent. — certain  fatty  mat- 
ters, albumen,  osmazone,  phosphorus  in  combination  with  fat,  sul- 
phur, and  phosphates  of  potash,  lime,  and  magnesia.  The  composition 
of  the  brain  of  animals,  the  dog,  the  sheep,  the  ox,  appears  to  be 
very  analogous  to  that  of  the  human  subject. 

Cellular  tissue  is  the  general  connecting  medium  throughout  the 
animal  body,  and  is  not  only  met  with,  it  may  be  said,  everywhere, 
but  forms  a  main  element  in  many  of  the  textures  of  the  body,  sucb 


BONES,  BLOOD.  381 

as  the  serous  and  mucors  membranes,  the  cartilages,  the  bones 
themselves,  which  are  in  fact  only  cellular  tissue  impregnated  with 
calcareous  salts.  Tendons  may  be  viewed  as  condensed  ropes  of 
cellular  tissue  ;  by  long  boiling  in  water  they  melt  entirely  into  gela- 
tine. 

Bones  consist  of  cellular  tissue,  as  stated,  resolvable  into  gelatine, 
and  of  a  large  proportion  of  saline  earthy  matter,  consisting  princi- 
pally of  phosphate  of  lime.  The  presence  of  this  phosphate  is  not 
extraordinary,  inasmuch  as  we  have  found  that  it  forms  an  element 
in  all  the  vegetables  upon  which  animals  are  supported.  By  boiling 
bones  even  reduced  to  powder  under  the  usual  pressure  of  the  atmo- 
sphere, but  a  small  quantity  of  their  gelatine  is  obtained ;  but  by  put- 
ting them  into  a  Papin's  digester,  and  subjecting  them  to  a  consider- 
ably higher  temperature  than  that  of  boiling  water,  we  can  dissolve 
the  whole,  or  nearly  the  whole  of  the  animal  matter,  and  leave  the 
earthy  parts  unchanged  ;  or  by  proceeding  in  another  way,  by  soaking 
bones  for  a  time  in  dilute  muriatic  acid,  we  can  dissolve  out  the 
earthy  matter,  and  leave  the  bone,  having  its  original  form  indeed, 
but  as  an  elastic,  pliant  gristle. 

The  relations  between  the  earthy  and  organic  matter  of  bone, 
vary  with  the  species,  but  especially  with  the  age  of  the  animal.  In 
early  life  the  cellular  element  predominates  ;  in  adult  age  the  salts 
predominate.  We  have  three  analyses  of  bone,  which  I  shall  here 
present : 

Man.  Ox.  Ox. 

Cartilage  susceptible  of  change  into  gelatine 33.3  33.3  50.0 

Sub-phospliiite  of  lime 53.0  57.4  37.0 

Carbonate  of  lime 11.8  3.9  10.0 

Phosphate  of  magnesia 1.2  2.0  1.2 

Soda,  and  a  trace  of  common  salt   1.2  3.4  " 

100.0  100.0  98.3 

Hair  has  a  very  complex  composition,  no  fewer  than  nine  different 
principles  or  substances  having  been  detected  in  its  constitution  ; 
among  the  number,  mucus,  various  oily  matters,  sulphur,  and  iron  ; 
wool,  fur,  and  horn,  are  all  similar  in  their  composition  to  hair. 

Bloody  in  all  the  higher  animals,  is  a  sluggish  fluid,  of  a  deep  red 
color  ;  in  many  of  the  inferior  tribes,  however,  such  as  insects,  crus- 
taceans, and  shell-fish,  it  is  limpid,  and  generally  colorless.  Under 
the  microscope,  red  blood  is  seen  to  consist  of  two  distinct  portions, 
a  serum  or  whey,  in  which  float  a  multitude  of  minute,  solid,  opaque 
corpuscles — the  globules  of  the  blood  of  physiologists,  particles  which 
have  different  characters  in  different  classes  of  animals. 

Blood  is  a  very  heterogeneous  compound.  Left  to  itself,  after 
being  drawn  from  a  vein,  it  sets  or  coagulates  into  a  soft  gelatinous 
solid,  which  by  and  by  begins  to  separate  into  two  portions,  one 
watery,  of  a  yellowish  color,  and  opalescent,  the  water,  whey,  or 
serum  ;  another  solid,  of  a  deep  red  or  reddish  brown  color,  the  clot 
or  coagulum.  The  watery  portion  contains  a  large  quantity  of  albu- 
men in  solution.  M.  Lecanu,  in  his  analysis  of  the  blood,  speaks  of 
as  many  as  twenty-five  different  substances  as  entering  into  its  cona- 
positioQ : 


882  BLOOD,  MILX. 


Water. 7904 

Oxygen,  azote,  free  carbonic  acid 

Iron 

Hydrochlorates  of  soda,  potash,  ammonU 

Sulphates  of  potash  and  of  poda 

Subcarbonate  of  lime  and  magnesia 

Phosphates  of  soda,  lime,  and  magnesia 

Lactate  of  soda 

A  soap,  having  soda  and  fixed  fat  acids  fcr  its  elements 

An  odorous,  volatile  salt,  a  fat  acid 

A  fatty  substance,  containing  phosphorus 

Cholesterine 

Scroll  ne 

Albumen  dissolved  in  the  water - 


IIJO 


67.8 
Globules  and  fibrine 130.8 


iooo.e 


The  blood  globules  consist  principally  of  albumen  combined  with 
a  little  fibrine  and  red  coloring  matter.  Any  difference  observed 
between  one  sample  of  blood  and  another,  is  connected  especially, 
almost  exclusively,  with  the  relative  proportions  of  the  liquid  part  or 
serum,  and  the  solid  part  or  clot.  The  solids  are  in  larger  propor- 
tion in  males  than  females,  in  grown-up  persons  than  in  aged  indi- 
viduals and  children,  in  subjects  well  and  abundantly  fed  than  in 
those  indifferently  supplied  with  food.  No  analysis  that  has  yet 
been  made  has  thrown  any  true  light  on  the  cause  of  the  difference 
of  color  perceived  between  arterial  and  venous  blood  ;  nevertheless, 
it  is  positively  known  that  it  is  by  the  concurrence  of  the  oxygen  of 
the  atmosphere  that  the  arterial  blood  in  the  living  body  acquires 
the  characters  which  distinguish  it,  and  that  carbonic  acid  gas  is 
evolved  or  thrown  off  in  the  course  of  the  action  that  takes  place. 

Ox  blood,  thoroughly  dried,  has  been  found  to  consist  of: 

Carbon 52.0 

Hydrogen 7.2 

Azote 15.1 

Oxygen 21.3 

Ash 4.4 

100.0 

Milk.  This  well-known  fluid  may  be  said  to  combine  in  itself  all 
the  organic  principles  and  mineral  substances  which  enter  into  the 
constitution  of  organized  beings.  Caseum,  identical  with  fibrine  and 
albumen,  fatty  matters,  sugar  of  milk,  and  different  salts,  among  the 
number  of  which  the  phosphates  stard  distinguished. 

The  ciseum,  the  sugar,  and  a  port:on  of  the  salts,  are  in  solution  ; 
the  fatty  matters  are  held  in  susper  sion  in  the  milk  in  the  form  of 
globules.  The  following  table  will  b^  found  useful,  as  giving  a  com-> 
prehensi  'c  survey  of  the  compositior  of  different  kinds  of  milk. 


MILK. 


383 


il. 

.• 

s  , 

a  . 

•5S2 

■5 

fu'^ 

-s 

Milk. 

1 

1 

!i 

Remarks. 

Authors  of  the 
analyses 

O  2 

Ui 

CO       «o 

Q 

Of  the  cow. . 

3.6 

4.0 

5.0 

87.4 

12.6 

Average     of    12  Le  Bel  and  Bous- 
analyses  at  Be-    singault. 
chclbronn. 

Of  the  cow. . 

3.8 

3.5 

6.1 

86.6 

13.4 

Average  of  6  an-:Q,uevenne. 

alyses  in  the  en- 

virons of  Paris. 

Of  the  cow. . 

4.5 

3.1 

5.4 

87.0 

13.0 

Idem. 

Henri  and  Chev- 
alier. 

Of  the  cow. . 

5.6 

3.6 

4.0 

86.8 

13.2 

Idem. 

Lecanu. 

Of  the  cow. . 

5.1 

3.0 

4.6 

87.3 

12.7 

An  analysis, 
Giessen. 

Haidlen. 

Of  the  ass... 

1.7 

1.4 

6.4 

90.5 

9.5 

Average  of  5  an-.P61igot. 

alyses.                | 

Of  woman... 

3.1 

3.4 

4.3 

89.2 

10.8 

Of  good  quality.  jHaidlen. 

Of  woman... 

2.7 

1.3 

3.2 

92.8 

7.2 

Of  middUng  qual-jHaidlen. 
ity.                     1 

Cow's  milk  always  shows  slight  alkaline  reaction ;  its  density  is 
about  1.03.  According  to  M.  Haidlen,  it  contains  no  salt  formed 
by  an  organic  acid,  no  lactates,  and  the  alkali  is  in  combination  with 
caseum,  the  solution  of  which  it  assists.  It  may  contain  about  a 
half  per  cent,  of  ash,  the  several  constituents  of  which  appear  to  be 
very  stable,  though  their  proportions  vary  greatly.  In  100  parts 
of  milk,  taken  from  two  different  cows,  Haidlen  found  the  following 
salts : 

Phosphate  of  lime    0.231  0.344 

Phosphate  of  magnesia 0.042  0.064 

Phosphate  of  iron 0.007  0.007 

Chloride  of  potassium 0.144  0.183 

Chloride  of  sodium 0.024  0.034 

Soda.... 0.042  0.045 

0.490  0.677 

As  cow's  milk  is  that  which  is  by  far  the  most  directly  interesting 
to  agriculture,  I  shall  enter  somewhat  particularly  into  its  history ; 
having,  however,  already  spoken  of  caseum,  its  distinguishing  con- 
stituent, and  albumen,  I  shall  here  confine  myself  to  the  subject  of 
the  sugar  and  the  oil  or  butter. 

Sugar  of  milk  is  prepared  for  commercial  purposes,  in  countriea 
or  districts  where  cheese-making  is  carried  on  to  a  great  extent, 
and  the  quantity  of  whey  at  command  is  very  large.  In  some  Can- 
tons of  Switzerland,  sugar  of  milk  is  obtained  by  simply  evaporating 
whey  properly  clarified,  to  the  consistence  of  sirup,  which  deposites 
the  sugar  in  the  crystalline  form  as  it  cools.  This  first  produce  is 
brown,  and  contaminated  with  various  impurities,  from  which  it  is 
freed  by  repeated  solutions  and  crystallizations.  It  then  becomes 
colorless,  transparent,  and  nearly  tasteless,  feeling  gritty  between 
the  teeth,  and  having  only  an  obscure  sweet  taste.  Ii  requires  from 
8  to  9  parts  of  cold  water  to  dissolve  it ;  in  hot  water  it  is  more 
soluble.     According  to  Proust,  it  consists  of : 


884  MILK. 

Carbon  40.0 

Hydrogen    6.7 

Oxygen 53.3 

100.0 

Buttct  To  understand  the  preparation  of  butter  thoroughly,  it 
is  absolutely  necessary  to  know  the  physical  constitution  of  the 
milk  from  which  it  is  obtained.  Now  the  microscope  shows  us  that 
milk  holds  in  suspension  an  infinity  of  globules  of  different  dimen- 
sions, which,  by  reason  of  their  less  specific  gravity,  tend  to  rise  to 
the  surface  of  the  liquid  in  which  they  float,  where  they  collect, 
and  by  and  by  form  a  film  or  layer  of  a  diflferent  character  from  the 
fluid  beneath  ;  the  superficial  layer  is  the  creairu,  and  this  removed, 
the  subjacent  liquid  constitutes  the  skim-milk.  This  separation  ap- 
pears to  take  place  most  completely  in  a  cool  temperature  from  54" 
to  60"  F. 

Allowed  to  stand  for  a  time,  which  varies  with  the  temperature, 
milk  becomes  sour,  and  by  and  by  separates  into  three  strata  or 
parts  :  cream,  whey,  and  curd,  or  coagulated  caseum.  By  suffering 
the  milk  to  become  acid  before  removing  the  cream,  it  has  been 
thought  that  a  larger  quantity  of  this,  the  most  valuable  constituent 
of  the  milk,  was  obtained ;  and  the  fact  is  probably  so  ;  but  in  dis- 
tricts where  the  subject  of  the  dairy  has  been  most  carefully  stud- 
ied, it  has  been  found  that  it  is  better  to  cream  before  the  appearance 
of  any  signs  of  acidity  have  appeared.  WTien  a  knife  can  be  push- 
ed through  the  cream,  and  withdrawn  without  any  milk  appearing, 
the  cream  ought  to  be  removed.* 

Butter  is  obtained  from  cream  by  churning,  as  all  the  world 
knows  ;  by  the  agitation,  the  fatty  particles  cohere  and  separate  from 
the  watery  portion,  at  first  in  smaller  and  then  in  larger  masses. 
The  remaining  fluid  is  buttermilk,  a  fluid  slightly  acid,  and  of  a  very 
agreeable  flavor,  containing  the  larger  portion  of  the  caseous  element 
of  the  cream  coagulated,  and  also  a  certain  portion  of  the  fatty 
principle  which  has  not  been  separated. 

The  globules  of  milk  appear,  from  the  latest  microscopical  ob- 
servations,f  to  be  formed  essentially  of  fatty  matter,  surrounded  with 
a  delicate,  elastic,  transparent  pellicle.  In  the  course  of  the  agita- 
tion or  trituration  of  churning,  these  delicate  pellicles  give  way,  and 
then  the  globules  of  oil  or  fatty  matter  are  left  free  to  cohere,  which 
they  were  prevented  from  doing  previously,  by  the  interposition  of 
the  delicate  film  or  covering  of  the  several  globules.  Were  the 
butter  simply  suspended  in  the  state  of  emulsion  in  the  milk,  we 
should  certainly  expect  that  it  would  separate  on  the  application  of 
heat ;  but  this  it  does  not :  cream  or  milk  may  be  brought  to  the 
boiling  point,  and  even  boiled  for  some  time,  without  a  particle  of 
oil  appearing.  Could  M.  Romanet  show  any  of  these  pellicles, 
apart  from  the  oil-globules  they  enclose,  it  would  be  very  satisfacto- 
ry, and  would  certainly  enable' us  to  explain  the  effect  of  churning 

Churning  is  a  longer  or  shorter  process,  according  to  a  variety  of 

*  Thaer,  Princlpes,  tc,  t.  iv.  p.  34L 
,  t  M.  Bomanet,  MSS. 


I 


MILK.  885 

circumstances  ;  it  succeeds  best  between  55  and  60*  F.  So  that, 
in  summer,  a  cool  place,  and  in  winter  a  warm  place,  is  chosen  for 
the  operation.  There  is  no  absorption  of  oxygen  during  the  process 
of  churning,  as  was  once  supposed  ;  the  operation  succeeds  perform- 
ed in  vacuo,  and  with  the  churn  filled  with  carbonic  acid  or  hydro- 
gen gas. 

On  being  taken  out  of  the  churn,  the  butter  is  kneaded  and  press- 
ed, and  even  washed  under  fair  water,  to  free  it  as  much  as  possible 
from  the  buttermilk  and  curd  which  it  always  contains,  and  to  the 
presence  of  which  must  be  ascribed  the  speedy  alteration  which 
butter  undergoes  in  warm  weather.  To  preserve  fresh  butter  it  is 
absolutely  necessary  to  melt  it,  in  order  to  get  rid  of  all  moisture, 
and  at  the  same  time  to  separate  the  caseous  portion.  This  is  the 
process  employed  to  keep  fresh  butter  in  all  the  warmer  countries 
of  the  world.  In  some  districts  of  the  continent,  it  is  also  had  re- 
course to  with  the  same  view.  The  butter  is  thrown  into  a  clean 
cast-iron  pot,  and  fire  is  applied.  By  and  by  the  melted  mass  enters 
into  violent  ebullition,  which  is  owing  to  the  disengagement  of  wa- 
tery vapor  ;  it  is  stirred  continually  to  favor  the  escape  of  the  steam, 
and  the  fire  is  moderated.  When  all  ebullition  has  ceased,  the  fire 
is  withdrawn,  and  the  melted  butter  is  run  upon  a  strainer,  by  which 
all  the  curd  is  retained.  M.  Clouet  has  proposed  to  clarify  butter 
by  melting  it  at  a  temperature  between  120°  and  140°  F.,  and  keep- 
ing it  so  long  melted  as  to  dissipate  the  water  and  secure  the  depo- 
sition of  the  cheesy  matter,  after  which  the  clear  melted  butter 
would  be  decanted.  I  doubt  whether  by  this  means  the  water  could 
be  sufficiently  got  rid  of,  a  very  important  condition  in  connection 
with  the  keeping  of  butter,  though  certainly  all  he  caseum  would 
be  deposited. 

The  moisture  and  curd  contained  in  fresh  butter  may  amount  to- 
gether to  about  18  per  cent. ;  at  least  we  find  that  we  lose  about  18 
lbs.  upon  every.  100  lbs.  weight  of  butter  which  we  melt  at  Bechel- 
bronn. 

The  information  which  we  have  on  the  produce  in  butter  and 
cheese,  from  different  samples  of  milk,  is  very  discordant,  so  that 
I  prefer  giving  the  results  of  a  single  experiment  made  under  my 
own  eyes.     From  100  lbs.  weight  of  milk,  we  obtained  : 

Cream 15.60  lbs 

White  curd  cheese 8.93    " 

Whey 75.47    " 

100.00 

The  15.60  lbs.  of  cream  yielded  by  churning : 

3.3  lbs.  butter,  or  21.2  per  cent.,  and 
12.27    "    buttermilk. 

The  reckoning  with  reference  to  100  lbs.  of  milk  consequently 
stands  thus : 

Cheese 8.93 

Butter 3.33 

Buttermilk 12.27 

Whey 75.47 

100.0 
33 


388  FOOD   AND   FEEDING. 

Taking  the  whole  of  the  milk  ootained  and  treated  at  differenl 
seasons  of  the  year,  I  find  that  36,000  lbs.  of  milk  yielded  1080  lbs. 
of  fresh  butter,  which  is  at  the  rate  of  3  per  cent.  From  the  state- 
ment of  M.  Baude,  it  appears  that  near  Geneva  a  proportion  of 
butter  so  high  as  3  per  cent,  is  never  obtained,  probably  because 
there  a  larger  projJortion  of  fatty  matter  is  left  in  the  cheese.  In 
the  dairy  of  Cartigny,  2200  gallons  of  milk  gave  : 

B'^tter 363  lbs.  or  about  1.6  per  cent, 

Gruye  re  cheese 1515         "  6.9        " 

Clot  from  the  whey,  obtained  by  boiling 1140         "  5.2       " 

In  the  same  neighborhood,  another  dairy,  that  of  Lullin,  gave  from 
the  same  quantity  of  milk  : 

Butter 4181bs.or  1.9  per  cent. 

Cheese 1485  67.5      " 

Clot  from  whey 968  4.4      "  * 

OF  THE  FOOD  OF  ANIMALS  AND  FEEDING. 

The  identity,  in  point  of  composition  and  properties,  which  ap- 
pears to  obtain  between  certain  substances  derived  from  either  king- 
dom of  nature,  naturally  led  to  the  conclusion  that  animals  do  not 
form  or  originate  the  substances  which  enter  into  their  organization, 
but  that  they  find  these  ready  formed  in  their  food,  and  merely  ap- 
propriate them ;  whence  we  must  conclude,  that  herbivorous  animals 
assimilate  several  of  the  proximate  principles  of  plants  immediately, 
causing  them  to  undergo  but  slight  modifications,  and  that  the  ele- 
ments of  the  animal  tissues  and  fluids  pre-exist  in  vegetables,  which 
further  contain  the  earthy  phosphate  that  forms  the  distinguishing 
characteristic  in  bone.t 

The  food  of  herbivorous  animals  must,  therefore,  always  contain, 
and  in  fact  always  contains,  four  essential  principles,  which,  by  their 
combination  or  reunion,  constitute  nutritious  matter,  properly  so 
called  : — 1st.  An  azotized  matter,  such  as  albumen,  caseine,  gluten, 
substances  which  are  probably  the  original  of  flesh.  '  2d.  An  oily  or 
fatty  matter,  which  approaches  more  or  less  closely  to  fatty  bodies 
in  general.  3d.  A  substance  having  a  ternary  composition,  sugar, 
gum,  fecula.  4th.  Certain  salts,  particularly  phosphates  of  lime, 
magnesia,  and  iron.  This  mixed  constitution,  which  a  forage  plant 
must  needs  offer,  justifies  the  general  ideas  propounded  by  Dr.  Prout 
on  nutrition.  This  able  chemist  has  said  that  milk  was  to  be  viewed 
as  the  standard  food,  and  that  all  alimentary  matters  must  resemble 
it  in  composition,  in  greater  or  less  degree  :  that  is  to  say,  besides 
phosphates,  food  must  contain  an  azotized  principle,  a  non-azotized 
principle,  and  a  fatty  body,  to  stand  in  lieu  of  caseum,  sugar,  and 
butter. 

The  fundamental  principle  that  animals  find  the  several  substances 
which  make  up  their  bodies,  ready  formed  in  the  substances  they 

*  In  all  the  dairy  counties  of  England,  the  milk  is  never  required,  like  the  ground,  ta 
five  a  double  crop ;  'I  yields  either  butter  or  cheese,  not  both.  Hence  the  greater  rich- 
ness of  English  cheese  In  general. — Eno.  Ed. 

t  Dumas  and  Boussingault.  The  Chemical  and  Physiological  Balance  of  Organl* 
Natnxe,  post  8vo.  London.  BalUiere,  1843.    (A  very  useful  little  work.— Eno.  Ed. J 


FOOD   AND    FEEDING.  387 

consume,  seems  very  well  calculated  to  assist  the  practical  farmer 
in  managinor  the  food  of  the  animals  upon  his  land  ;  for  if  flesh,  fat, 
and  bone  exist  all  but  ready  formed  in  the  food,  it  is  obvious  that 
the  best  kind  will  be  that  precisely  which,  under  the  same  weight, 
contains  the  largest  quantity  of  the  various  matters  of  the  organi- 
zation. 

It  is  by  no  means  easy  to  ascertain  precisely  the  amount  of  the 
azotized  constituents,  gluten,  and  albumen,  contained  in  plants ;  to 
do  so  requires  both  time  and  pains.  But  let  it  be  once  admitted  that 
the  nutritive  properties  of  forage  increase  in  the  precise  ratio  of 
these  matters,  this  is  clearly  as  much  as  to  say  that  the  value  is  in 
proportion  to  the  quantity  of  azote  contained  in  the  food,  and  that  it 
becomes  a  matter  of  the  highest  moment  to  have  at  hand  a  ready 
mode  of  determining  the  point.  I  believe  it  infinitely  better  to  get 
at  the  quantity  of  azote  immediately,  which  is  easily  done,  than  by 
any  roundabout  and  laborious  process  to  ascertain  the  amount  of 
albumen  and  gluten  :  the  quantity  of  azote  ascertained,  it  is  most 
easy  to  deduce  the  quantity  of  albumen  and  gluten — in  other  words, 
o^ flesh — contained  in  each  particular  species  of  food  examined  ;  for, 
as  a  general  rule,  vegetable  food  does  not  contain  any  other  azotized 
principle.  It  is  true,  indeed,  that  all  the  azotized  principles  of  vege- 
table origin  cannot  be  considered  as  nutritious ;  some  of  them,  on 
the  contrary,  are  virulent  poisons  or  active  medicines,  according  to 
the  dose  in  which  they  are  administered.  But  these  poisonous  sub- 
stances are  not  met  with  in  appreciable  quantity  in  the  plants  which 
are  commonly  grown  for  the  food  either  of  man  or  beast.  Still,  all 
the  truly  nutritious  articles  of  food  contain  an  azotized  principle. 
The  experiments  of  M.  Magendie  have  shown,  that  substances  which 
contain  no  azote,  such  as  sugar,  starch,  oil,  will  not  support  life ; 
and,  on  the  other  hand,  it  is  ascertained  that  the  quality  of  alimentary 
matter,  flour  for  example,  increases  with  the  amount  of  gluten  which 
it  contains.  It  is  because  the  seeds  of  the  leguminous  vegetables 
are  richer  in  azotized  principles — that  is,  in  flesh — that  they  are  also 
more  highly  nutritious  than  the  seeds  of  the  cereals. 

These  several  considerations,  therefore,  induce  me  to  conclude; 
that  the  nutritious  principles  of  plants  and  their  products  reside  in 
their  azotized  principles^  and  consequently  that  their  nutritious  pow- 
ers are  in  proportion  to  the  quantity  of  azote  they  contain.  From 
what  precedes,  however,  it  is  obvious  that  I  am  far  from  regarding 
azotized  principles  alone  as  sufficient  for  the  nutrition  of  animals ; 
but  it  is  a  fact,  that  every  highly  azotized  vegetable  nutritive  sub- 
stance is  generally  accompanied  by  the  other  organic  and  inorganic 
substances  which  concur  in  nutrition. 

In  seeking  to  learn  the  precise  quantity  of  azote  contained  in  a 
great  number  of  articles  used  as  food  for  cattle,  I  have  had  it  in 
view  particularly  to  find  a  standard  or  fixed  point  for  estimating  their 
comparative  nutritive  properties.  It  is  long  since  more  than  one  of 
the  most  distinguished  farmers,  both  of  England  and  Germany, 
essayed  to  resolve  this  important  problem  in  rural  economy.  Thua 
Thaer  and  many  others  have  given  tables  of  the  quantities  by  weight 


888  FOOD   AND   FEEDING. 

in  which  one  article  of  alimentation  might  be  substituted  for  another 
These  tables  are  in  'ict  tables  of  equivalents  with  reference  to  food 
But  it  is  unfortunate  that  there  should  be  considerable  diversity  of 
statement  among  thnr  authors.  Yet,  even  up  to  the  present  time, 
it  could  not  well  have  been  otherwise,  and  these  discrepancies  will 
only  surprise  those  who  are  unacquainted  with  the  difficulties  of  the 
subject.  One  grand  cause  of  difference  probably  exists  in  the  de- 
gree of  dryness  of  the  article  subjected  to  experiment.  The  nature 
of  the  soil,  a  very  dry  or  very  rainy  season,  the  climate,  &c.,  must 
all  be  regarded  as  so  many  causes  influencing  the  quantity  of  water 
contained  in  plants,  and  in  consequence  their  actual  nutritive  quali- 
ties. The  only  sure  mode  of  proceeding,  in  short,  appears  .o  be,  to 
reduce  the  several  articles  to  a  state  of  complete  dryness,  and  to 
make  their  quantity  in  this  condition  the  first  element  in  the  reckoning. 
I  may  state,  that  the  theoretical  data  obtained  by  proceeding  in  this 
way  have  already  been  approved  by  practical  applications. 

Hay  may  be  assumed  as  the  most  common  or  universally  used  of 
all  kinds  of  fodder  :  it  is  in  some  sort  the  staple  food  of  the  animals 
that  are  particularly  attached  to  an  agricultural  concern,  and  may 
therefore  be  appropriately  made  the  standard  of  comparison  for  all 
other  kinds  of  food  or  forage.  Hay  itself,  however,  varies  greatly 
in  point  of  quality  :  in  assuming  it  as  the  standard,  I  have  therefore 
to  state,  that  meadow  hay  of  good  quality  is  to  be  understood.  The 
analyses  which  I  have  made  of  this  article  at  different  times,  satisfy 
me  that  in  the  state  in  which  it  is  commonly  used,  it  contains  from 
1.0  to  1.5  of  azote  per  cent.  In  choosing  a  specimen  for  analysis, 
it  is,  of  course,  highly  necessary  that  it  be  an  average  specimen  ; 
that  it  consist  of  equal  or  rather  relative  proportions  of  the  several 
elements  which  enter  into  its  constitution,  such  as  stalks,  leaves, 
flowers,  and  seeds.  Taking  a  sample  of  hay,  for  instance,  weighing 
exactly  5  lbs.  avoird.,  I  found  that  it  was  made  up  of — 

Hard  woody  stems 2.393  lbs. 

Bottoms  of  leaves  and  very  fine  stems 0.847 

Flowers,  leaves,  and  a  few  seeds 1.760 

5.000 

The  ultimate  analysis  of  which  gave  : 

Of  azote  per  cent. >...1.19 

Military  contract  hay  of  1840  gave  of  azote  per  cent 1.21 

Hay  made  in  Alsace  in  18:J5  "  "         1.04 

Hay  made  in  Alsace  in  1837  "  "         1.15 

Average  of  azote  per  100 1.15 

Hay,  as  it  is  generally  used,  contains  from  11  to  12  per  cent,  of 
water,  which  is  got  rid  of  by  thorough  drying.  And  as  albumen, 
caseum,  and  vegetable  gluten  contain  16  per  cet)t.  of  azote,  we 
perceive  that  the  azotized  matter  which  is  the  representative  of 
flesh,  in  hay  may  be  represented  by  the  number  7.2  per  cent.  Hay 
does  not,  indeed,  always  contain  so  much  azote  ;  that  which  is  won 
from  marshy  lands  contains  much  less  ;  and  again  there  are  samples 
.hat  contain  more.  After-math,  or  second-crop  hay,  is  certainly 
more  nutritious  than  first-crop  hay,  a  fact  which  we  have  ascertained 


POOD   AND   FEEDTNG.  389 

rej€atedly  at  Bechelbronn  ;  but  this  hay  is  nevertheless  held  less 
suitable  for  horses,  probably  because,  being  made  late  in  the  season, 
it  is  commonly  stacked  more  or  less  damp,  and  suffers  change  in 
conscjuence  : 

After-math  hay  gave 2.0    per  cent,  of  azote 

A  choice  siiinpie  'f  the  best  hay 1.29  " 

The  flower  or  ear,  containing  little  woody  stem- ..  •  2.1  " 

These  examples  suffice  to  show,  that  when  an  animal  is  to  be  put 
upon  another  kind  of  food  than  hay,  it  is  very  necessary  to  take  the 
quality  of  the  latter  article,  which  has  been  employed,  into  the  ac- 
count. In  the  table  which  I  shall  immediately  present,  I  have  as- 
sumed good  meadow-hay,  containing  1.15  of  azote  and  11  of  water 
per  cent,  for  my  standard.  The  importance  of  a  table  of  equivalents 
for  forage  has  long  been  felt  by  farmers ;  and  they  who  have  given 
their  attention  to  the  accumulation  of  data  for  its  construction,  de- 
serve our  best  thanks.  The  use  of  a  table  of  equivalents  is  extreme- 
ly simple  :  the  numbers  placed  underneath  the  value  of  hay  in- 
dicate the  weights  of  the  several  kinds  of  forage  named  in  the  first 
column,  which  may  respectively  be  substituted  for  100  parts  of  hay 
by  weight.  Thus,  according  to  Block,  366  lbs.  of  carrots  may  be 
substituted  for  100  lbs.  of  meadow-hay.  Pabst  holds  60  lbs.  of  oats 
to  be  equivalent  to  100  lbs.  of  hay.  If  the  question  be  to  replace 
7.26  or  7|  lbs.  of  oats  in  the  ration  of  a  horse  by  Jerusalem  arti- 
chokes, we  find  in  the  table  that  60  of  oats  are  equivalent  to  274 
Jerusalem  potatoes,  and  we  therefore  infer  that  35.2,  say  35|  lbs. 
is  the  weight  of  the  root  to  be  substituted  for  that  of  the  oats. 

Certain  information  on  the  nutritive  value  of  the  various  articles 
consumed  by  cattle  as  food,  is  really  of  high  importance  in  rural 
economy  :  it  is  obviously  the  only  guide  for  the  feeder  in  the  use  or 
purchase  of  forage.  Let  us  suppose,  for  example,  that  a  measure  of 
potatoes  (22  gallons)  weighing  165  lbs.  is  worth  lOd.  at  market, 
and  that  hay  is  worth  2*.  6c^.  the  cwt. ;  2  cwts.  or  rather  220  lbs. 
would  cost  5s.  Let  us  now  admit,  on  theoretical  grounds,  that  this 
quantity  of  hay  is  equivalent  to  693  lbs.  of  potatoes;  it  plainly  ap- 
pears, on  looking  at  the  cost  of  these  equivalents,  that  there  would 
be  a  positive  advantage  in  using  potatoes,  inasmuch  as  they  are 
worth  no  more  than  3^.  6^d.  There  would  indeed  be  money  to  be 
made  by  selling  hay,  and  purchasing  its  equivalent  in  potatoes. 

The  equivalents  which  I  have  deduced  from  my  elementary  ana- 
lyses, agree  on  many  occasions  with  the  conclusions  of  practical 
men  ;  in  others,  they  differ  notably  from  them  ;  at  the  same  time  it 
must  be  observed,  that  the  practical  equivalents  differ  from  one 
another  in  at  least  an  equal  degree.  We  see,  for  instance,  that 
Schnee  and  Thaer  think  220  lbs.  of  hay  will  be  replaced  by  1405 
lbs.  of  wheat  straw,  while  Flottow  gives  429  lbs.  as  the  equivalent 
number.  According  to  Mayer,  630  lbs.  of  turnip  are  equivalent  to 
220  lbs.  of  hay,  while  Middleton  gives  1760  as  the  equivalent  num- 
ber of  turnips,  a  number  which  coincides  remarkably  with  that  infer- 
red from  theory.  Block  assigns  66  as  the  equivalent  number  of 
peas.     Thaer  makes  it  more  than  twice  as  high,  viz.  145.     Mangel 

33* 


390  POOD   AND   FEEDINO. 

wurzel,  according  to  Thaer,  is  represented  by  1012 ;  while  Mayei 
and  Pabst  call  it  but  550,  ^ud  M.  de  Dombasle  states  it  a  little  high- 
er, viz.  574.  However  highly  we  estimate  the  difficulties  of  com- 
ing to  accurate  conclusions  on  the  subject  of  alimentation  or  feeding, 
it  is  not  easy  to  account  for  such  discrepancies  among  practical 
men  ;  and  then,  as  to  the  astonishing  similarity  which  their  conclu. 
sions  bear  to  one  another  upon  many  heads,  it  is  impossible  to  over- 
look the  fact,  that  the  resemblance  is  far  more  in  appearance  than 
in  fact ;  for  it  is  notorious,  that  the  generality  of  those  who  have 
committed  themselves  to  writing  have  generally  copied  each  other. 
Indeed,  it  is  not  always  very  obvious  whether  the  equivalent  number 
which  we  find  assumed,  has  been  determined  by  the  farmer  from  his 
own  observation  or  experience,  or  has  been  adopted  from  some  other 
observer.  No  one  who  is  not  a  total  stranger  to  the  art  of  making 
experiments  will  ever  be  brought  to  believe  that  eleven  experiment- 
ers, operating  separately,  could  have  fallen  plump  upon  the  number 
90  as  the  equivalent  for  lucern,  or  even  that  any  five  of  them  could 
have  lighted  upon  600,  neither  more  nor  less,  as  the  equivalent  num- 
ber for  cabbage ! 

The  method  which  I  have  myself  pursued,  that  namely  of  infer- 
ring the  nutritious  quality  from  the  contents  in  azote,  is  far  from 
being  free  from  objection ;  on  the  whole,  it  may  be  said  to  place  the 
equivalents  somewhat  too  low,  inasmuch  as  by  the  process  of  ele- 
mentary analysis,  the  quantity  of  azote  is  apt  to  come  out  a  little  too 
high,  some  portion  of  it  being  derived  from  the  nitrates  present  in 
vegetables,  which  are  certainly  of  no  avail  in  nutrition.  This  is  the 
source  to  which  I  ascribe  the  anomaly  presented  by  the  leaves  of 
mangel-wurzel.  And,  then,  it  is  not  to  be  forgotten  that  in  dosing 
the  azote  we  have  regard  but  to  the  jlesh  contained  in  the  article  of 
food,  which  although  unquestionably  the  principle  that  is  of  highest 
value,  and  the  one  which  is  apt  to  be  most  deficient,  is  still  not  all. 
The  neutral  non-azotized  substances,  starch,  sugar,  gum,  oil,  are  in- 
dispensable as  auxiliaries  in  the  alimentation  of  cattle ;  the  three 
first  undergo  changes  in  the  course  of  the  digestive  process  which 
fit  them  to  be  absorbed  immediately,  and  the  oil  is  brought  to  the 
state  of  an  emulsion,  and  so  is  taken  up  and  adds  to  the  fat.  The 
woody  fibre  alone  of  vegetables  appears  to  have  no  direct  share  iu 
the  nutrition  of  animals  ;  it  is  discovered  almost  or  altogether  un- 
changed in  the  dejections. 

It  is  therefore  every  thing  but  matter  of  indifference  whether  a  par- 
ticular article  of  forage  contains  a  larger  or  a  smaller  proportion  of 
starch,  sugar,  &c.,  associated  with  a  given  quantity  of  azoti/ed  or 
truly  animalized  matter.  The  potato  and  meadow-hay  brought  to 
the  same  state  of  dryness,  contain  as  nearly  as  possible  the  same 
proportions  of  azote — from  1.3  to  1.5  per  cent.;  in  other  words,  about 
8^  per  cent,  of  albumen  and  gluten,  i.  e.,  of  flesh.  But  in  the  pota- 
to, almost  the  whole  of  the  9U  per  cent,  of  the  remainder  consists 
of  starch ;  while  in  hay  it  is  woody  fibre,  inert  matter  as  we  must 
presume  it,  that  is  present  in  by  far  the  largest  proportion.  And 
this  explains  the  higher  value  of  the  same  weight  of  dry  potato  a4 


FOOD   AND    FEEDING.  391 

an  aiticle  of  sustenance.  To  give  our  theoretical  equivalents  all 
the  precision  that  is  really  desirable,  it  would  be  necessary  to  as- 
certain the  quantity  of  organic  matter  which  escaped  digestion  with 
reference  to  each  particular  species  of  food.  This  is  an  inquiry 
which  it  is  my  purpose  to  enter  upon  by  a:nd  by.  The  labor  com- 
pleted, we  should  then  be  in  possession  of  tables  in  regard  to  the 
proportion  of  the  non-azotized  as  well  as  the  azotized  principles ; 
and  further,  to  the  quantity  of  inert  matter  which  it  would  be  proper 
to  deduct  from  the  weight  of  the  ration  allowed  in  each  case. 

To  have  determined  the  azote  in  an  article  of  food,  then,  is  not 
to  have  done  all  that  is  strictly  necessary  :  still  azote  is  the  scatea 
element  in  all  kinds  of  vegetable  food;  starch,  gum,  sugar,  pectine, 
oil,  are  universally  present,  and  generally  in  adequate  quantity.  A.s 
articles,  as  unlike  one  another  as  possible,  I  have  mentioned  pota- 
toes and  meadow  hay.  Now  the  theory  indicates  300  of  the  root  for 
100  of  the  dried  grass ;  and  I  can  state  positively,  from  long  and  re- 
peated observation,  that  it  is  not  advisable  in  practice  to  substitute 
less  than  280  of  potatoes  for  100  of  meadow-hay. 

The  state  of  dryness  of  certain  kinds  of  forage  may  have  a  mark- 
ed influence  on  their  nutritious  qualities.  They  may  even  decline 
in  nutritive  value  by  the  process  of  drying,  so  that  analysis  of  itself 
may  lead  us  into  error  in  regard  to  the  nutritive  value  of  dry  articles 
of  food.  Breeders  have  in  fact  long  suspected  that  green  fodder  is 
more  nutritious  than  dry  fodder;  that  grass,  clover,  &c.,  lose  nutri- 
tious matter  by  being  made  into  hay.  That  the  thing  is  so  in  fact, 
appears  to  have  been  demonstrated  by  a  skilful  agriculturist,  well 
acquainted  with  the  ait  of  experimenting,*  who  found  that  9  lbs.  of 
green  lucern  were  quite  equal  in  foddering  sheep  to  3^^^  lbs  of  the 
same  forage  made  into  hay,  while  he  at  the  same  time  ascertained 
that  9  lbs.  of  green  lucern  would  not  on  an  average  yield  more  than 
2.02  lbs.  of  hay.  In  allowing  each  sheep  3i^jj^  lbs.  of  lucern  hay  as 
its  ration,  consequently,  it  was  as  if  the  animal  had  had  14.34  or 
more  than  14|  lbs.  of  the  green  vegetable  for  its  allowance. 

These  practical  facts  are  obviously  of  great  importance  ;  they 
prove  beyond  a  shadow  of  doubt  that  the  belief  of  agriculturists  in 
general  as  to  the  immense  advantages  of  consuming  clover  and  lu- 
cern as  green  meat  is  well  founded.  Nor  is  this  all ;  it  is  not  mere- 
ly the  absolutely  greater  feeding  value  of  the  crop  green  than  of  the 
crop  dried  and  made  into  hay ;  there  is  further,  the  saving  of  ex- 
pense in  making  the  hay,  and  still  further,  the  escape  of  all  risk  from 
loss  through  bad  weather  during  the  process,  by  which  that  wiiich 
was  valuable  fodder  but  a  few  days  before,  may  become  fit  only  for 
the  dung-hill.  Still,  because  100  of  green  clover  or  lucern  repre- 
sent 2-3  of  the  same  articles  dried,  it  does  not  follow  that  the  feeding 
properties  of  the  fodder  in  each  of  the  two  states  can  be  truly  re- 
presented by  the  ratios  of  these  numbers  to  one  another.  Messrs. 
Perrault  find  from  their  experiments  that  the  true  relation  is  8  to  3. 
By  assuming  71.5  lbs.  as  the  quantity  of  dry  forage  obtained  from 

•  M.  PterraBlt  de  Jotemps,  in  Jcmrn.  d'Agricult.  v.  iii.  p.  97. 


892  FOOD   AND   FEEDING. 

220  lbs.  of  gretu  clover  or  lucern,  the  quantity  which  is  actually 
obtained  on  an  average,  the  ratio  comes  out  8  to  2.G,  a  number  which 
falls  somewhat  short  of  that  which  is  assumed,  but  not  much.  With 
regard  to  the  difference  in  the  feeding  or  nutritive  value  of  green 
and  dried  fodder,  the  loss  may  in  a  general  way  be  ascribed  to  loss 
of  the  more  substantia]  parts  of  the  plants  especially  experienced  in 
the  process  of  drying.  This  is  the  conclusion,  at  all  events,  to  which 
M.  Crud  came  ;  I  have  myself,  however,  found  that  clover-hay, 
made  in  the  field  and  ricked  in  the  usual  way,  had  not  the  same 
nutritive  value  as  a  quantity  of  the  same  crop  carefully  dried  :n  the 
laboratory. 

By  way  of  pendant  to  the  conclusions  of  Messrs.  Perrault,  from 
their  valuable  observations,  I  shall  here  add  the  average  of  some 
experiments  that  were  made  at  Bechelbronn,  in  1841,  on  the  eon- 
version  of  clover  into  clover-hay.  The  clover  crops  of  this  season 
were  magnificent ;  the  plant  in  its  second  year  growing  to  more  than 
a  yard  in  height.  Green  clover  on  the  average  may  be  considered 
as  consisting  of: 

Clover-hay 29.85 

Water 70.15 

100.00 

As  extremes  in  our  experiments  of  1841,  we  add : 

Clover-hay 35.7  25.0 

Water 64.3  76.0 

100.0  100.0 

Analysis  gave  the  number  75  as  the  nutritive  equivalent  number 
of  clover-hay.  Assuming  76  to  represent  the  moisture  lost  during 
the  drying,  the  equivalent  becomes  311  for  the  same  fodder  in  the 
green  state,  meadow-hay,  the  standard,  being  100. 

But  practice  is  not  here  in  harmony  with  theory ;  the  value  of 
clover-hay,  in  point  of  nutritive  power,  is  found  not  to  differ  essen- 
tially from  that  of  meadow-hay ;  and  the  equivalent  of  green  clover 
is  generally  placed  between  425  and  500.  And  I  may  say,  that 
daily  experience  in  the  stable  tends  to  show  that  the  theoretical 
equivalent  of  clover-hay  is  too  high,  that  its  nutritious  properties  are 
not  so  great  as  they  are  inferred  to  be.  From  a  mean  of  four 
weighings,  I  find  that  four  cows  upon  green  clover  consume  2499 
lbs.,  or  624f  lbs.  each  per  diem.  The  usual  allowance  to  one  of 
our  cows,  however,  is  33  lbs.  of  hay  of  good  quality  ;  from  which 
it  would  follow,  that  the  equivalent  of  green  clover  would  be  445. 
But  the  animals  on  the  green  fodder  fattened  apace,  and  every  thing 
showed  that  they  were  very  differently  nourished  than  they  would 
have  been  with  their  33  lbs.  of  meadow-hay.  According  to  theo- 
retical data,  each  cow  in  its  624|  lbs.  of  green  food  per  day  received 
an  equivalent  of  47.3  lbs.  of  hay  ;  and  if  it  be  considered,  that  during 
the  season  of  green  forage  they  have  it  almost  at  will,  it  must  be 
conceded  that  during  this  period  the  quantity  of  food  consumed  ii 
actually  greater  than  when  it  is  regularly  doled  out.    .A^dditional  ex- 


FOOD   AND    FEEDING.  393 

pcriments  are  therefore  necessary  to  decide  the  question  as  to 
whether  forage  eaten  green  is  really  more  nutritious  than  the  same 
forage  consumed  when  converted  into  hay.  For  my  own  part,  I 
should  not  be  surprised,  from  what  I  have  seen,  were  it  found  that 
dry  fodder,  previously  moistened  and  carefully  portioned  out,  wa? 
actually  more  nourishing  than  the  same  food  would  have  been  had 
it  been  eaten  green.  Green  forage,  of  a  very  soft  or  watery  nature, 
is  notoriously  possessed  of  purgative  properties,  which  must  lessen 
its  value  as  food  ;  but  my  observation  leads  me  to  say,  on  he  othei 
hand,  that  animals  kept  upon  dry  fodder  require  more  care  with  re- 
gard to  watering  than  is  generally  bestowed  upon  them.  The  abso- 
lute necessity  of  a  sufficient  degree  of  moistness  in  the  food,  in  order 
to  secure  its  due  and  easy  digestion,  greatly  countenances  the  prac- 
tice which  is  beginning  to  be  introduced  in  some  places  of  steeping 
hay  for  some  time  in  water  before  giving  it  to  cattle.  This  neces- 
sity further  explains  the  great  advantages  in  associating  with  dried 
fodder  other  very  watery  articles,  such  as  roots  and  tubers,  turnips 
and  field-beet,  potatoes  and  Jerusalem  artichokes. 

The  oleaginous  seeds  contain  a  considerable  proportion  of  animal- 
ized  matter,  similar  in  composition  and  qualities  to  the  caseum  of 
milk ;  and  the  cake  which  comes  from  the  oil-mill  retains  almost 
the  whole  of  this  substance.  The  proportion  of  from  0.05  to  0.06 
of  azote,  indicates  nearly  42  per  cent,  of  the  representative  of  flesh 
m  oil-cake.  Theory,  in  fact,  rates  the  nutritious  power  of  this  sub- 
stance so  high,  that  100  of  hay  may  be  replaced  by  from  22  to  27 
of  cake. 

The  almost  universal  use  of  oil-cake  in  the  feeding  and  fattening 
of  cattle,  is  of  itself  sufficient  evidence  of  its  highly  nutritive  quali- 
ties. It  has  even  been  found  possible  to  keep  sheep  and  oxen  upon 
this  food  almost  exclusively.  M.  Bouscaren  finding  considerable 
difficulty  in  getting  rid  of  his  oil-cake,  thought  of  associating  with 
his  oil-mill  an  establishment  for  feeding  cattle  ;  and  he  found  that 
oxen  put  up  to  fatten  throve  perfectly  upon  a  mixture  of  the  refuse 
of  the  wine-press  and  oil-cake.  Cows,  upon  a  diet  of  this  kind,  give 
on  an  average  12^  pints  of  milk  per  diem.  The  allowance  per  head 
is  about  15  lbs.  of  oil-cake  in  three  meals,  given  each  time  imme- 
diately after  the  animals  have  been  watered,  and  in  the  interval, 
each  is  allowed  about  12  lbs.  of  straw  or  chaff.  The  cake  broken 
in  pieces  is  steeped  in  water,  and  worked  up  into  a  paste  of  the 
consistency  of  dough.  If  the  animals  show  any  disinclination  to 
this  food  at  first,  they  are  brought  to  like  it  by  having  a  ball  of  it, 
the  size  of  the  fist,  administered  to  them  two  or  three  times. 

Supposing  that  the  cows  fed  in  this  way  would  be  adequately 
maintained  upon  33  lbs.  of  hay,  and  that  13  lbs.  of  straw  are  equiv- 
alent to  3  lbs.  of  hay,  it  appears  that  in  the  allowance  given,  15  lbs. 
of  oil-cake  will  supply  the  place  of  30  lbs.  of  hay  ;  the  equivalent 
of  the  cake,  therefore,  is  51.5,  a  number  very  different  from  the  22 
deduced  from  analysis.  The  equivalents  of  those  who  have  sought 
to  appreciate  the  alimentary  value  of  oil-cake  are,  however,  suffi- 
ciently at  variance  with  one  another.     It  will  be  seen  in  the  table, 


894  FOOD   AND  FEEDING. 

that  the  numbers  assigned  by  different  authorities  are  42,  57,  and 
108 ;  and  M.  Perranlt,  Tom  direct  experiment,  found  the  equivalent 
number  of  colza-cake  t*  be  36,  analysis  giving  23  as  the  theoretical 
number.  On  the  whole  it  may  be  said,  that  in  practice,  the  results, 
although  sufficiently  different,  still  agree  in  ascribing  to  oil-cake  a 
nutritive  value  inferior  to  that  indicated  by  theory. 

I  have  thought  it  important  to  insist  upon  the  discrepancy  which 
is  here  so  conspicuous  between  the  inferences  from  chemical  analy- 
sis and  those  arrived  at  by  experience,  because  it  appears  to  me  to 
depend  upon  a  particular  circumstance  which  frequently  intervenes 
in  the  feeding  of  cattle,  and  which  it  is  very  important  to  be  aware 
of;  I  allude  to  the  influence  of  the  bulk  of  the  allowance  of  food. 

Vegetable  food  of  every  description  has  nearly  the  same  specific 
gravity  ;  it  is  but  little  above  that  of  water  ;  the  bulk  of  the  allow- 
ance therefore  depends  upon  its  weight.  Every  one  will  conceive 
that  a  ration  of  highly  nutritious  food,  which  for  this  reason  would 
occupy  but  little  space,  would  be  open  to  many  objections.  A  cart- 
horse, of  the  ordinary  size,  from  what  I  have  myself  repeatedly 
observed,  requires  from  26  to  33  lbs.  of  solid  food,  and  about  the 
same  quantity  of  water  in  the  twenty-four  hours.  The  bulk  of  this 
allowance,  when  masticated  and  brought  to  the  state  in  which  it  is 
swallowed,  will  be  upwards  of  9^  cubic  feet.  Now,  if  for  the  ordi- 
nary forage,  one  that  is  five  times  more  nutritious  were  substituted, 
oil-cake,  for  example,  the  dry  ration,  according  to  the  rule  of  equiv- 
alents, would  be  reduced  to  6.6,  or  a  Mttle  more  than  4^  lbs.,  and  its 
bulk  would  not  surpass  5^  cubic  feet.  The  animal  would  not  feel 
satisfied  with  this  allowance,  it  would  still  feel  hungry,  or  the  food 
given  in  such  a  concentrated  shape  would  disagree  with  it.  If,  on 
the  contrary,  a  forage  that  is  very  little  nutritious  were  substituted, 
such  as  wheat-straw,  the  equivalent  of  which  is  500,  the  ration 
would  then  become  too  bulky  to  be  eaten  in  the  course  of  a  day,  it 
would  amount  to  as  many  as  165  lbs.  It  is  therefore  absolutely  ne- 
cessary to  take  into  consideration  the  bulk  of  the  food  allowed  :  the 
belly  must  of  necessity  be  filled ;  whatever  the  nutritive  value  of 
any  article,  it  must  be  given  in  a  certain  quantity  ;  and  in  the  case 
of  such  a  substance  as  oil-cake,  the  consumption  to  fill  the  stomach 
would  cease  to  be  in  any  kind  of  proportion  to  the  nutritive  equiv- 
alent. 

It  is  extremely  difficult  to  appreciate  the  precise  limits  beyond 
which  an  article  of  forage  or  a  given  ration  ceases  to  be  nutritious. 
When  any  addition  is  made  to  an  allowance  known  and  admitted  to 
be  sufficient,  the  effect  of  the  extra  quantity  is  scarcely  perceptible ; 
so  that,  in  practice,  we  are  apt  to  fall  into  the  error  of  estimating  at 
too  low  a  rate  the  nutritious  powers  of  food  given  in  too  large  quan- 
tities. I  have  had  proof  of  this  in  a  series  of  experiments  on  the 
maintenance  of  a  number  of  milch-kine.  To  a  cow  which  was 
receiving  the  equivalent  of  33  lbs.  of  meadow-hay  in  dry  fodder  and 
Jerusalem  potatoes,  an  addition  was  made  of  6|  lbs.  of  oil-cake,  by 
which  the  allowance  of  nourishment  was  doubled  theoretically  ;  the 
4oiraal  (Mily  ate  the  half  of  the  cake,  howfever  :  still,  the  quality  of 


FOOD   AND   FEEDINa.  -•  895 

the  milk  was  not  improved.  Experience  heie  would  oompe.  os  to 
set  down  the  3^  lbs.  of  cake  consumed  as  nil ;  yet  it  is  positively 
ascertained  that  tlie  article  is  one  of"  the  most  substantial  known. 

The  hard  and  husky  grain  which  is  given  to  cattle  frequently 
escapes  digestion,  because  it  has  escaped  the  teeth — a  circumstance 
which  leads  to  the  formation  of  an  estimate  of  its  nutritious  quali- 
ties inferior  to  those  it  actually  possesses.  To  prevent  this  loss, 
oats  are  now  often  bruised,  as  are  beans  and  peas  also ;  or  they  are 
mixed  with  chopped  hay  or  straw,  which  the  animals  are  compelled 
to  chew  thoroughly  before  they  can  swallow  it ;  or  the  corn  is 
steamed  or  steeped  in  boiling  water  before  it  is  put  into  the  manger. 
Some  experiments  that  were  instituted  by  order  of  the  French  vete- 
rinary commission,  however,  seemed  to  show,  that  the  loss  of  corn 
from  passing  through  the  stomach  and  bowels  unchanged  was  really 
so  trifling,  that  it  might  be  safely  left  out  of  the  account. 

Tubers  and  roots  are  invaluable  fodder  for  horned  cattle,  and  in 
the  course  of  the  winter,  come  instead  of  hay  to  a  considerable 
extent.  Our  experience  at  Bechelbronn  also  enables  us  to  say,  that 
horses  are  readily  brought  to  a  regimen  of  the  same  description, 
which,  judiciously  instituted,  becomes  the  means  of  great  economy 
in  the  maintenance  of  these  animals. 

Roots,  turnips,  and  mangel-wurzel,  are  frequently  thrown  down 
whole  before  the  animals.  It  is  vastly  better ;  nay,  it  is  so  much 
better  that  it  ought  to  be  made  an  invariable  rule  never  to  give  them 
save  cut  into  slices  and  mixed  with  cut  straw  or  chaff.  There  is 
always  a  great  advantage  in  combining  any  very  soft  and  watery 
article  of  food  with  one  that  is  dry  and  hard,  to  say  nothing  of  the 
chaff  absorbing  and  rendering  useful  the  juices  that  would  escape 
and  be  lost. 

Mangel-wurzel,  turnips,  carrots,  and  Jerusalem  potatoes,  are 
always  given  raw.  The  potato  is  frequently  steamed  or  boiled  first ; 
yet  I  can  say  positively  that  horned  cattle  do  extremely  well  upon 
raw  potatoes ;  and  at  Bechelbronn,  our  cows  never  have  them  other- 
wise than  raw  :  they  are  never  boiled,  save  for  horses  and  hogs. 
The  best  mode  of  dealing  with  them  is  to  steam  them ;  they  need 
never  be  thoroughly  boiled  as  when  they  are  to  serve  for  the  food 
of  man.  The  steamed  or  boiled  potatoes  are  crushed  between  two 
rollers,  or  simply  broken  with  a  wooden  spade  or  dolly,  and  mixed 
with  cut  hay  or  straw  or  chaff  before  being  served  out.  It  may  not 
be  unnecessary  to  observe,  that  by  steaming,  potatoes  lose  no  weight ; 
whence  we  conclude  that  the  nutritive  equivalent  for  the  boiled  is 
the  same  as  that  for  the  raw  tuber.  Nevertheless,  it  is  possible  that 
the  amylaceous  principle  is  rendered  more  readily  assimilable  by 
boiling,  and  that  by  this  means  the  tubers  actually  become  more 
nutritious.  Some  have  proposed  to  roast  potatoes  in  the  oven  ;  and 
there  can  be  little  question  but  that,  treated  in  this  way,  they  answ^er 
admirably  for  f^*tening  hogs  or  even  oxen.  Done  in  the  oven,  pota- 
toes may  be  brought  into  a  state  in  which  they  may  perfectly  supply 
the  place  of  corn  in  the  foddering  of  horses  and  other  cattle. 
There  is  but  the  expense  of  the  firing  to  be  taken  into  the  a/Ccouat 


396  FOOD   AND    FEEDING. 

The  only  mode  of  ascertaining  the  favorable  or  unfavorable  influ- 
ence of  any  particular  system  of  diet  or  regimen  upon  animals,  ia 
by  weighing  them.  In  ref  rd  to  full-grown  animals  performing 
regular  work,  such  as  cart  a;.d  plough  horses,  and  to  milch-kine,  the 
allowance  ought  to  be  such  as  will  maintain  them  at  the  same  or 
nearly  the  same  weight.  Any  thing  like  stinting  is  immediately 
followed  by  loss  of  flesh  and  of  weight,  of  strength  and  spirit,  in  the 
animal.  The  allowance  being  continued  the  same,  similar  effects 
will  follow  any  increase  of  work,  any  exaction  of  unusual  eifort  on 
the  part  of  the  animal.  An  essential  condition,  therefore,  in  all 
experiments  on  the  due  dieting  or  feeding  of  animals,  is,  that  they  be 
performed  under  precisely  similar  conditions  of  labor.  Young  ani- 
mals receiving  a  sufficiency  of  wholesome  food,  increase  from  day 
to  day  by  a  quantity  which  we  shall  have  occasion  immex.iately  to 
mention  ;  and  all  changes  of  regimen  are  followed  at  once  by  notable 
variations  in  the  ratio  of  the  growth ;  if  the  new  regimen  be  less 
nutritious  than  that  which  went  before  it,  the  balance  immediately 
proclaims  the  fact. 

Cattle  put  up  to  fatten  are  always  supplied  with  a  superfluity  of 
fodder  ;  the  excess  may  be  regarded  as  an  addition  to  the  quantity 
requisite  to  maintain  them  in  health  and  strength.  The  increase  in 
the  weight  of  an  animal  is  often  so  great  within  a  given  time,  as  to 
be  very  appreciable  by  weighings  made  even  at  very  close  intervals  ; 
the  balance  also  shows  us  that  the  rate  of  increase  varies  at  different 
periods  of  the  interval  during  which  the  fattening  is  going  on.  An 
animal  put  up  to  fatten  for  the  butcher,  is  not  the  best  subject  for 
coming  to  conclusions  upon  in  regard  to  the  nutritive  value  of  dif- 
ferent articles  of  sustenance  ;  still  it  is  useful,  in  a  practical  point 
of  view,  to  determine  the  influence  of  this  and  of  that  course  of 
regimen  on  the  production  of  fat.  Any  misapplication  of  nutritive 
equivalents  is  speedily  proclaimed  by  the  animal's  losing  weight, 
instead  of  maintaining  or  gaining  upon  the  amount  to  which  it  had 
attained. 

When  the  quantity  of  fodder  has  been  ascertained  which  an  ani- 
mal ought  to  have  in  the  twenty-four  hours  to  maintain  it  in  full 
health  and  vigor,  or  that  may  be  necessary  to  enable  it  to  lay  on 
additional  flesh  and  fat,  it  is  to  be  weighed,  and  the  article  or  mix- 
ture of  articles  which  it  is  the  business  of  the  experimenter  to  try, 
is  to  be  given  in  part  or  in  whole.  After  the  lapse  of  a  certain 
time  the  animal  is  weighed  again,  and  the  weight  upon  this  occasion 
enables  us  to  say  whether  the  new  or  amended  ration  is  superior, 
equal,  or  inferior,  to  that  which  had  preceded  it.  Such  is  the  pro- 
cedure generally  followed :  but  in  putting  it  in  practice  myself,  I 
saw  that  it  was  liable  to  lead  to  rather  serious  mistakes,  which  I 
then  used  every  effort  to  diminish  or  to  nullify  in  the  experiments 
which  I  undertook  on  the  keep  of  horses — experiments  which  I 
^hink  interesting  enough  to  deserve  being  particularly  related. 

In  a  considerable  number  of  observations  with  which  I  had  be- 

>me  familiar,  I  saw  that  the  course  had  not  always  been  continued 
4r  a  sufficierJ    length  of  time  ;   so  that  changes  which  were  the 


POOD   AND   FEEDING. 


897 


effect  of  more  accident  must  frequently  have  boen  ascribed  to  the 
effects  of  regimen.  In  a  general  way,  it  is  acknowledged  that  an 
adult  animal,  upon  the  ration  that  is  known  to  be  adequate  for  its 
maintenance,  returns  at  the  same  hour  every  day  to  the  yesterday's 
weight :  this,  however,  is  only  strictly  true  in  reference  to  a  series 
of  weighings  continued  through  a  number  of  days,  to  make  any 
irregularity  between  one  weighing  and  another  disappear. 

With  a  view  to  discovering  the  amount  of  variation  which  an 
animal  experiences  in  point  of  weight  when  it  is  fed  in  the  same 
uniform  manner,  is  foddered  precisely  at  the  same  hours,  &c.,  I 
weighed  a  horse  and  a  mare,  which  were  leading  the  most  regular 
and  unvaried  life  possible,  for  they  were  both  employed  in  working 
an  exhausting  machine  for  several  days  in  succession,  the  weighings 
being  performed  at  noon  each  day  before  they  were  watered,  and 
from  four  to  five  hours  after  their  breakfast.  Here  are  the  results 
in  a  tabular  form  : 


Date  of  the  weighings. 

Weight  of  the 
horse. 

Weight  of  the 
mare. 

kil.         lbs.  avoird. 
453.0             996.6 
4.55.0 
456.0 
454.0 

449.0            988.9 
449.5 
449.0 
454.0 

454.0             998.8 
459.5           1010.9 
448.0             985.6 
452.0             994.4 
454.0 
448.0 
452.5 

kil.         lbs.  avoird. 
494.0           1086.8 
497.0 
497.0 

497.5           1092.7 
487.0 
487.5 
492.0 
496.5 
484.5           1065.9 

490.5 

496.0 

491.0 

484.0           1064.8 

491.0 

17         •«            '<    ,...         

18         "            "     

19          "             "     

21          «'             "     

22          «'             "     

23          "             "     

24          "            "     

25          ««            «<     ....         

27          "             "     

28          "             "     

29          ««             «'     

30          "             "     

31          "             "     

4.52.0             994.4 
459.5           1010.9 
448.0             985.6 

491.8           1081.9 
497.5           1092.7 
484.0           1064.8 

Greatest  difference  above  the  mean 

Greatest  difference  below  the  mean 

Difference  between  the  extreme  weights.. 

16.5 

8.8 
7.7 

10.8 
17.1 
6.3 

Another  horse  (Old  Fox)  12  years  old,  taken  fasting,  at  four 
o'clock  in  the  morning  of  the  28th  of  April,  1842,  weighed  1051 
lbs.  ;  at  the  same  hour  of  the  29th,  he  weighed  1060  lbs.  ;  ditto  on 
the  29th,  1038  lbs. 

It  is  obvious,  therefore,  that  a  horse  foddered  most  regularly  and 
weighed  at  the  same  hour,  nevertheless  presents  differences  in  his 
weight  that  may  amount  to  nearly  30  lbs.  ;  and  which,  without  as- 
surance of  this  fact,  we  should  be  disposed  to  ascribe  to  the  effect 
of  our  regimen.  This  is  enough  to  satisfy  us  that  in  all  experi- 
ments upon  feeding,  it  is  absolutely  necessary  to  carry  them  on  for 
some  considerable  time,  in  order  to  escape,  or  at  all  events  to  lessen 
the  errors  that  would  be  introduced  into  the  conclusions  by  these  ac- 
cidental differences  of  weight.     They  may  vary  with  reference  to 

34 


8d8  MAINTENANCE    OF    ANIMALS. 

different  animals  ;  they  are  necessarily  smalkr  in  amount  among 
those  that  are  young  and  small,  such  as  calves  and  sheep,  than  in 
adult  oxen  and  horses;  hi.-,  they  do  not  occur  the  less  on  that  ac- 
count, and  must,  therefore,  occasion  errors  of  the  same  description. 
What,  then,  shall  we  say  ot"  those  small  variations  in  the  weight  in 
a  ewe  or  a  ram,  amounting  perhaps  to  1^  or  2  lbs.,  ascertained  in 
the  course  of  an  experiment  carried  over  two  or  three  days,  though 
conducted  with  the  most  scrupulous  attention  to  accuracy  in  the 
world  ?  That  they  may  very  possibly  have  been  purely  accidental. 
The  first  in  every  series  of  experiments  on  the  maintenance  of 
animals,  ought  in  fact  to  have  it  in  view  to  ascertain  the  amount  of 
accidental  variation  in  the  weight  of  the  creatures  which  are  their 
subjects  ;  as  this  variation  is  now  on  this  side  now  on  that,  there  is 
an  obvious  advantage  in  having  a  certain  number  upon  trial  at  a 
time  ;  any  error  that  occurs  will  thus  be  more  apt  to  be  corrected  ; 
and  the  results  may  be  held  more  worthy  of  confidence  in  propor- 
tion as  the  numbers  have  been  large  from  which  they  have  been  de- 
duced Another  cause  of  error,  which  I  had  occasion  to  discover 
in  the  course  of  my  experiments,  appears  to  be  connected  with  the 
weight  of  the  allowance.  Equal  in  nutritious  value,  difl^erent  allow- 
ances may  still  have  very  diflferent  weights ;  it  is  obvious,  that  a  ra- 
tion of  hay  and  corn  will  weigh  much  less  than  its  equivalent  in 
roots,  tubers,  or  green  meat.  Animals  that  have  been  kept  for  some 
time  upon  a  dry  diet,  if  put  on  one  that  is  very  bulky  and  watery, 
will  immediately  increase  very  considerably  in  weight  ;  and  their 
increase  is  both  so  sudden  and  so  great,  that  it  is  impossible  to  as- 
cribe it  to  augmented  nutrition,  to  liesh  and  fat  laid  on.  The  ani- 
mals are  simply  distended,  their  paunch  and  bowels  are  filled  with  a 
larger  quantity  of  food  than  they  were  before  ;  and  the  state  of  dis- 
tension continues,  though  it  suffers  accidental  variations,  so  long  as 
the  new  course  of  feeding  is  persisted  in.  In  opposite  circum- 
stances, as  when  animals  that  have  been  long  upon  soft  and  watery 
food,  are  suddenly  put  upon  hard  diet,  they  always  drop  very  con- 
siderably in  weight.  These  sudden  changes  throw  disorder  and 
contradiction  into  the  conclusions,  and  puzzled  me  greatly  until  I 
discovered  their  cause.  It  is  obvious  that  no  kind  of  reliance  can 
be  placed  upon  the  conclusions  which  have  been  come  to  from  single 
weighings  made  at  the  end  of  each  particular  course  of  alimentation. 
To  get  at  results  which  shall  be  worthy  of  any  credit,  the  animals 
that  are  to  be  made  the  subjects  of  experiment  must  be  fed  for  sev- 
eral days  upon  the  particular  ration  that  is  to  be  approved,  in  order 
to  be  brought  to  the  state  of  body  which  may  be  said  to  belong  in 
particular  to  each  system  of  dieting,  before  being  weighed  ;  it  is 
only  when  this  is  attained,  indeed,  that  the  experiment  can  be  held 
to  be  properly  begun  ;  and  then  it  is  to  be  continued  for  a  sufficient 
length  of  time  to  lessen  the  influence  of  those  accidental  variations 
of  weight,  of  which  I  have  spoken  so  particularly.  It  is  perhaps 
oeedless  to  observe,  that  any  increase  in  weight  and  the  maintenance 
of  that  increase,  are  not  always  of  themselves  sufficient  signs  for 
affirmmg  that  the  course  then   followed  is  superior  or  equal  to  tbe 


MAINTENANCE    OF   ANIMALS.  399 

one  which  preceded  it.  Various  other  circumstances  of  divers  char- 
acter must  be  taken  into  the  reckoning,  and  in  particular  the  state 
of  the  animals.  It  is  very  necessary  to  have  an  eye  to  the  state  of 
the  coat,  to  the  spirit  or  liveliness  of  the  animal,  to  the  nature  of  the 
dejections,  the  size  of  the  belly,  the  disposition  of  draught  animals 
for  their  w^ork,  the  quantity  of  milk  given  by  milch-kine,  &c.  Nev- 
ertheless, and  as  a  general  proposition,  it  may  be  said  that  a  station- 
ary condition,  or  a  slight  increase  of  weight,  is  almost  always  in 
favor  of  the  course  along  with  which  it  is  gained  or  maintained, 
while  any  loss  is  almost  always  an  indication  of  an  inadequate  al- 
lowance or  of  deficient  nutritive  qualities  in  the  ration,  taken  in  con- 
nection with  the  work  required  or  the  milk  obtained. 

The  experiments  which  I  am  about  to  detail  were  undertaken  to 
determine  the  nutritive  value  of  a  variety  of  forages  associated  with 
the  ordinary  articles  in  keeping  the  horse.  The  great  dearth  of  for- 
age that  was  felt  in  Alsace,  in  consequence  of  the  extraordinary 
droughts  of  1840,  led  us  to  feel  the  full  importance  of  researches  in 
this  direction  ;  for  then  we  were  compelled  to  replace  by  potatoes  a 
very  large  proportion  of  the  hay  usually  consumed  in  the  stable. 
And,  indeed,  by  assuming  the  theoretical  equivalent  as  the  basis  of 
this  substitution,  I  found  that  I  saved  money  by  the  course,  at  the 
same  time  that  the  health  and  strength  of  my  draught  cattle  were 
maintained  unimpaired.  Still,  as  every  quesvion  that  bears  upon  the 
keep  of  the  animals  attached  to  a  farm  is  too  important  to  be  left  to 
the  decision  of  theory  alone,  I  thought  it  imperative  on  me  to  con- 
trol the  inferences  of  chemical  analysis  by  the  results  of  experience. 

The  best  food  for  horses  has  long  been  admitted  to  be  hay  and 
oats  in  combination  ;  neither  article  alone  would  have  the  same 
happy  effect  that  the  two  together  produce.  A  ration  of  hay  alone 
would  be  too  bulky  ;  one  of  oats  alone  would  not  be  bulky  enough. 
But  the  horse  is  not  particular  in  his  food.  Barley  in  southern 
countries  replaces  oats,  and  answers  equally  well.  I  have  my- 
self kept  horses  and  mules  for  long  periods  of  time  on  maize  and 
the  tops  of  sugar  canes  exclusively  ;  and  on  the  elevated  table- 
lands of  the  Andes,  and  in  the  steppes  of  South  America,  the 
horses,  though  they  do  much  hard  work,  are  kept  wholly  on  green 
meat.  Much  of  course  depends  on  the  way  in  which  the  animal 
has  been  brought  up. 

In  the  circumstances  in  which  we  are  generally  placed  in  this 
country,  I  do  not  imagine  that  there  would  be  any  actual  advantage 
in  replacing  the  ordinary  food  of  our  horses  by  roots  and  tubers ;  I 
doubt  even  whether  the  substitution  would  have  good  effects.  I 
know,  indeed,  that  horses  have  been  kept  through  the  winter  upon 
potatoes  and  mangel-wurzel ;  but  it  is  a  different  matter  to  feed  an 
animal  and  keep  him  standing  quiet  in  the  stable  without  work,  and 
to  feed  him  at  the  same  time  that  a  certain  quantity  of  labor  is  re- 
quired of  him  every  day.  A  horse  in  full  work  would  scarcely  get 
through  the  bulky  ration,  which  should  consist  of  beet»root  alone ; 
his  meal-times  are  restricted ;  if  he  has  certain  hours  for  his  work, 

has  he  certain  hours  for  his  breakfast,  dinner,  and  supper  also. 


400  MAINTENANCE    OF    ANIMALS. 

This  is  one  reason  why  carriers'  horses  and  pi'St-horses,  horses,  in 
a  word,  which  have  long  and  severe  work  to  perform,  receive  the 
larger  portion  of  their  allowance  in  corn.  The  inconveniences  of 
bulky  rations  are  much  less  felt  in  the  cov/-house  than  in  the  stable  ; 
not  to  speak  of  their  particular  organization,  which  actually  enables 
them  to  take  in  a  much  larger  quantity  of  food  than  the  horse,  the 
steer  and  the  cow  have  always  a  longer  time  allowed  them  for  their 
meals  than  are  regularly  given  to  the  horse. 

The  experience  of  nearly  a  whole  year  having  satisfied  me  that  a 
cart-horse  may  have  half  his  ration  in  roots  or  tubers,  I  set  out  from 
this  fact  in  the  experiments  which  I  instituted. 

EXPERIMENTS    ON  THE    MAINTENANCE    OF    HORSES  WITH   MIXED    FOOD. 

The  usual  allowance  to  a  horse  at  Bechelbronn  for  the  twenty- 
four  hours  consists  of : 

Hay  .        .    22    lbs. 

Straw  .         .         .  5J 

Oats        .        .        .        .       7i 

With  this  ration  the  teams  are  kept  in  excellent  condition.  Two 
teams  were  selected  as  subjects  of  experiment,  each  consisting  of 
four  horses  ;  these  I  shall  distinguish  by  the  titles.  Team  No.  1 
and  Team  No.  2.  Each  remained  under  the  care  of  the  same  ser- 
vant throughout.     Team  No.  1  was  composed  of: 

Braun,  a  mare,  7  years  old. 

Schimmel,  a  horse,  7  " 

Hans,  do.,  16  « 

Gaty,  do.,         8  " 

Team  No.  2  was  composed  of : 

Old  Fox,  a  mare,  16  years  old, 

Braun,  do.,  5  " 

Nickel,         do.,  14  " 

Hengst,  a  horse,  5  " 

EXPERIMENT  I. 

One  half  the  allowance  of  hay  was  replaced  by  potatoes  lightly 
steamed ;  280  of  the  tubers  being  assumed,  according  to  theory,  as 
equivalent  to  100  of  hay.     The  ration,  therefore,  consisted  of: 

Hay         .         .         .         .11    lbs. 

Straw  .         .         .  5i 

Oats        .         .         .         .       7j 

Potatoes  .         .         .         30  8-10 

The  potatoes  were  broken  down  and  mixed  with  chopped  straw, 
and  never  put  into  the  mangers  until  cold. 

From  accidental  circumstances,  particularly  bad  weather  during 
the  course  of  the  autumnal  labors,  the  teams  were  exposed  to  very 
hard  work,  an  event  which  of  course  throws  uncertainty  over  the 
results  of  this  trial.     After  having  been  upon  the  course  of  food  in- 


MAINi-ENANCE    OF    ANIMALS.  401 

dicated  for  a  few  days,  the  teams  were  weighed  once,  and  again 
after  an  interval  of  twenty-four  hours : 

Team  No.  1.  No.  2.  Both  teams.      Mean  per  horse. 

First  weighing 4617.8  4461  9079.4  1134.9 

Second  weighing 4554.0  4334  8888.0  1111.0 

In  24  hours loss       63.8  127  191.4  23.9 

The  loss  experienced  here  authorized  me  to  conclude,  that  the  al- 
lowance under  the  circumstances  was  not  sufficient.  The  30.8  lbs. 
of  steamed  potatoes  could  not  have  adequately  replaced  the  11  lbs. 
of  hay ;  it  would  have  been  highly  interesting  to  have  ascertained 
how  horses  kept  on  the  standard  and  usual  allowance  would  have 
stood  the  same  amount  of  fatigue.  Unfortunately  this  comparison 
could  not  be  made,  all  the  horses  in  the  stable  having  been  put  on 
the  potato  regimen  at  the  same  time.  There  is  this  much  to  be  said 
for  the  particular  course  tried,  however,  that  the  animals  did  their 
work  with  great  spirit,  and  continued  in  excellent  health. 

EXPERIMENT  II. 

INTRODUCTION    OF    JERUSALEM   f  OTATOES    INTO    THE    RATION. 

Jerusalem  potatoes  are  held  excellent  food  for  the  horse  ;  they  are 
eaten  greedily,  and  he  thrives  on  them.  In  this  second  experiment, 
30/oths  lbs.  of  Jerusalems  cut  into  slices  were  substituted  for  11 
lbs.  of  hay,  the  same  theoretical  equivalents  being  assumed  for  them 
as  for  the  common  potato.     The  ration  now  consisted  of: 

Hay         ....     11    lbs. 

Straw  .         .■        .  5i 

Oats        .         .         .         .       7j 

Jerusalem  potatoes       .         30.8 

Having  been  accustomed  to  this  regimen  for  some  days,  the 
teams  were  weighed,  and  having  gone  on  for  eleven  days  they  were 
weighed  again  : 

Team  No.  1.  No.  2.  Both  teams.        Means  per  horse. 

First  weighing 4556  3245  8901  1112.7 

Second  weighing 4611  3412  8923  1113.6 

In  11  days gain      55        loss    33       gain    22        gain      0.9 

A  result  which  leads  to  the  conclusion,  that  the  equivalent  as- 
sumed for  the  Jerusalem  potato  was  correct ;  the  animals  had  done 
their  work,  and  gained,  one  with  another,  f^ths  of  a  pound  in 
weight. 

EXPERIMENT  III. 

RATION  OF  HAY  AND  POTATOES. 

Eleven  pounds  of  hay,  in  the  usual  allowance,  were  replaced  by 
30.8  lbs.  of  potatoes  ;  the  whole  of  the  oats  and  straw,  by  15.4  lbs 
of  hay.  These  substitutions  were  made  upon  the  supposition,  that 
100  of  hay  was  equivalent  to  280  of  potatoes,  to  50  of  oats,  and  to 
630  of  straw.     The  ration,  then,  was  composed  as  follows  : 

Hay 26.6  lb*. 

Potatoes 30.8  " 

34* 


402  MAINTENANCE  OF  ANIMALS. 

This  was  a  ration  which  it  was  the  more  interesting  to  try,  from 
the  circumstance  of  Professor  Liebig*  having  come  to  the  conclu- 
sion, from  certain  theoretical  views,  that  it  must  be  impossible  to 
keep  horses  in  health  and  strength  upon  hay  and  potatoes  exclusively. 
The  experiment  was  continued  for  a  fortnight : 

Team  of  No.  1.        No.  f.        Both  teams.       Mean  weight  per  hone. 

First  weighing 4620  4312  8932  1116.5 

Second  weighing 4675  4697  9372  1171.5 

In  14  days gain    55  385  440  55.0 

In  one  fortnight,  consequently,  the  weight  of  eight  horses  had  in- 
creased by  an  aggregate  sum  of  440  lbs.,  or  55  lbs.  per  head — an 
increase  at  the  rate  of,  as  nearly  as  possible,  3.9,  say  4  lbs.  per  diem ; 
and  allowing  the  greatest  latitude  for  error,  it  seems  that  we  cannot 
estimate  the  increase  per  head  at  less  than  1.76,  say  If  lbs.  per 
diem.  The  condition  of  the  horses  was  most  satisfactory  ;  the  de- 
jections were  healthy  in  appearance ;  the  only  inconvenience  ob- 
served was,  the  considerable  bulk  of  the  allowance,  and  the  addi- 
tional time  which  had  to  be  given  the  teams  to  their  meals.  This 
inconvenience  was  particularl}^  obvious  in  the  case  of  the  older 
horses.  Besides  the  two  experimental  lots,  other  twelve  horses 
were  put  upon  the  same  regimen,  and  with  the  same  good  effects. 
The  equivalents  adopted  in  the  composition  of  the  ration,  in  this 
third  experiment,  may  therefore  be  regarded  with  perfect  confidence 
as  suitable.  Experience,  indeed,  would  rather  lead  us  to  conclude, 
that  the  nutritive  power  of  the  potato  had  been  estimated  at  some- 
what too  low  a  rate. 

EXPERIMENT  IV. 

SUBSTITUTION  OF  OATS  AND  STRAW  FOR  A  PORTION  OF  THE  HAY. 

The  ration  here  consisted  of: 

Hay 11    lbs. 

Straw 11      " 

Oats 12.1   " 

The  horses,  having  been  two  days  on  this  diet,  were  weighed. 
The  experiment  was  continued  for  eleven  days : 

Team  No.  1.         No.  S.  Both  teams.       Arera^  per  hone 

First  weighing 4584.8  4348.3  8933.1  1116.7 

Second  weighing 4593.6  4352.7  8946.3  lllSi! 

In  11  days gain       8.8  4.4  13.2  1.5 

Under  this  regimen,  consequently,  the  weight  of  the  teams  re- 
mained very  nearly  the  same  as  it  was  before  beginning  the  experi- 
ment ;  still  there  was  something  gained. 

In  conducting  this  experiment,  we  had  an  opportunity  of  observing 
how  important  it  is  to  habituate  the  animals  to  their  new  regimen 
before  weighing  for  the  first  time.  Had  this  precaution  been  neg- 
'ected,  the  result  would  hav«  come  out  against  the  ration,  for  the 
animals  were  found,  when  first  entered  on  it,  to  weigh  together  as 
many  as  9372  lbs.,  and  two  days  afterwards  no  more  than  8933  lbs., 

*  Afiictiltaxal  chemistry. 


MAINTENANCE  OF  ANIMALS.  40S 

which  would  have  indicated  a  loss  of  449  lbs. ;  the  difference  being 
due,  however,  in  great  part,  or  entirely,  to  the  less  bulky  or  weighty 
food  employed. 

EXPERIMENT  V. 

POTATOES  SUBSTITUTED  FOR  A  PORTION  OP  THE  HAY. 

The  ration  made  use  of  in  the  first  experiment  looks  so  well,  in 
reference  to  economy  of  hay,  and,  indeed,  answered  so  well  under 
the  peculiar  circumstances  in  whi^ch  it  was  tried,  that  I  thought  it 
would  be  advisable  to  try  it  again  when  the  horses  were  doing  ordi- 
nary work.     The  ration  consisted  of: 

Hay 11  Ihs. 

Straw....    5.5       " 

Oats 7.23     " 

Steamed  potatoes 30.8       " 

The  first  weighing  took  place  after  the  horses  had  been  over  a 
week  on  the  ration,  and  the  experiment  was  continued  for  63  days. 
In  team  No.  1,  Braun,  from  indisposition,  had  been  replaced  by 
Rapp,  a  horse  nine  years  old,  and  weighing  1157  lbs.  : 


Team  No.  I. 
....   4425 

No.  2. 
4362 
4428 

Bott  teams. 
8348 
8929 

Averag^e  weight  per  hone. 

Second  weighing.. 

....  4501 

1116.2 

In  63  days gain      76  66  81  10.1 

In  the  course  of  two  months,  consequently,  on  a  ration  in  which 
11  lbs.  of  hay  were  replaced  by  30.8  lbs.  o.^  dressed  potatoes,  the 
weight  of  the  horses  may  be  said  to  have  been  more  than  main- 
tained. This  experiment  seems  to  show  satisfactorily,  that  the 
equivalent  of  the  potato  cannot  be  far  from  the  number  280. 

EXPERIMENT  VI. 

JERUSALEM  POTATO  FOR  A  PORTION  OF  THE  HAY. 

The  horses  were  brought  back  to  the  same  conditions  as  in  the 
second  experiment,  30.8  lbs.  of  Jerusalem.^  being  substituted  for 
11  lbs.  of  hay.  The  team  No.  2  was  alone  subjected  to  this  experi- 
ment, being  kept  on  it  for  16  days,  and  first  weighed  after  having 
had  it  for  some  time  : 

First  weighing No.  2.       4395    lbs.        Average  weight  per  horse    1098.9 

Second  weighing..      "  4396.7  "  "  "  1099.1 

Iniedays gain         1.7  0.2 

This  result  confirms  that  which  was  elicited  by  the  second  ex- 
periment. 

EXPERIMENT  VH. 

INTRODUCTION   OF    FIELD-BEET,    OR   MANGEL-WURZEL,    INTO   THE 
RATION. 

Horses  readily  get  accustomed  to  field-beet.  The  root  is  sliced, 
and  mixed  with  chaff,  (cut  straw.)  For  11  lbs.  of  hay,  which  I  re- 
trenched, I  allowed  44  lbs.  of  beet ;  i.  e.  I  took  400  as  the  equiva- 
lent numbei  of  ^.he  root.     The  ration  consisted  as  under: 


404  MAINTENANCE  OF  ANIMALS. 

Hay 11    lbs. 

Straw  5.5   " 

Oats 7.2   " 

Beet, 44.0   " 

A  horse,  after  having:  been  kept  on  this  diet  for  some  time,  wai 
weighed  ;  and  the  regimen  having  been  continued  for  a  fortnight,  he 
was  weighed  again  : 

First  weighing 1014.0  lbs. 

Second  weighing 1023.0    " 

In  a  fortnight gain        9.4 

This  horse  was  all  the  while  doing  rather  hard  but  very  regular 
work ;  for  eight  hours  every  day  he  was  in  the  shafts  of  a  grinding 
mill.     He  did  not  alter  in  condition  ;  the  dejections  were  healthy. 

During  the  winter  of  1841-2,  our  cows  ate  a  considerable  propor- 
tion of  our  beet ;  and,  as  a  substitute  for  the  33  lbs.  of  meadow-hay, 
which  is  their  usual  allowance,  we  gave  72|  lbs.  of  beet.  The  ration 
then  stood  thus : 

Hay 22    lbs. 

Beet 72.6  " 

Straw 4.4  " 

Upon  this  regimen,  the  weight  of  the  inmates  of  one  of  our  stables 
i»as: 

On  the  29th  January 24615  lbs. 

On  the  21st  April 26488 

Increase  due  to  births  and  to  growth 1837 

It  thus  appears  that,  in  foddering  kine,  the  quantity  of  beet  allow- 
ed with  advantage  may  be  large  ;  but  it  is  also  obvious,  that  the 
nutritive  value  of  the  root  is  not  great.  At  Bechelbronn,  at  all 
events,  we  found  it  requisite  to  replace  9  or  10  of  hay  by  40  of  root. 
Our  beet,  it  is  true,  contains  but  12  per  cent,  of  dry  matter  ;  in  other 
places,  where  the  proportion  of  dry  substance  to  the  water  is  larger, 
it  is  possible  that  a  smaller  proportion  would  be  found  to  answer  the 
end. 

EXPERIMENT  VIII. 

INTRODUCTION    OF  THE  SWEDISH  TURNIP  INTO  THE  RATION  AND 
REPLACING  A  PORTION  OF  THE  HAY. 

Swedish  turnip,  combined  with  some  dry  forage,  answers  excel- 
lently with  the  horse.  Analysis,  indicating  280  as  the  equivalent 
of  this  article,  two  horses  were  put  upon  the  following  ration,  in 
which  11  lbs.  of  the  usual  allowance  of  hay  were  replaced  by  Swe- 
dish turnip  : 

Hay nibs. 

Straw 5.5 

Oats 7.2 

Swedes....   30.8 

It  was  obvious  before  the  lapse  of  but  a  few  days,  that  the  horses 
were  falling  off  upon  this  regimen,  that  they  were  not  fed  ;  and  on 
weighing  them,  this  plainly  appeared  : 

First  weighing 2283,6  Aver,  of  each  horse  1141,8 

Second  weighing,  9  diys  afterwards 2178,0  "  1089,0 

LotslnQdays .105.6  SZ.i 


MAINTENANCE   OF   ANIMALS.  405 

The  equivalent  for  the  Swedish  turnip  adopted,  had  therefore  been 
too  high ;  the  allowance  was  not  sufficient.  This  led  me  to  analyze 
the  article  again  ;  and  I  discovered  that  the  true  equivalent  of  the 
sample  with  which  I  was  operating,  was  at  least  676,  and  not  280 
as  1  had  presumed  before.  Indeed,  in  another  experiment  with  the 
same  pair  of  horses  where  the  equivalent  of  Swedish  turnip  was  as- 
sumed at  400,  I  found  that  though  the  animals  kept  up  their  weight 
at  the  point  to  which  it  had  fallen,  they  gained  nothing ;  whence  it 
may  be  safely  inferred  that  the  No.  400  was  still  too  low,  and  that 
the  new  equivalent  676  is  nearer  the  truth. 
EXPERIMENT  IX. 

INTRODUCTION  OF  CARROTS  INTO  THE  RATION. 

Horses  are  extremely  fond  of  carrots  ;  and  there  is  no  root  per- 
haps, the  nutritious  qualities  of  which  have  been  more  vaunted  or 
exaggerated.  Yet,  analysis  appears  to  indicate  that  350  of  carrot 
are  required  to  replace  100  of  good  meadow-hay.  On  one  occasion, 
in  the  stable  at  Bechelbronn,  when  the  potato  in  one  of  our  rations 
was  replaced  by  an  equal  weight  of  carrots,  the  eifect  was  highly 
disadvantageous  ;  and  even  in  following  the  theoretical  equivalent 
of  the  carrot  (350)  we  had  still  no  reason  to  be  perfectly  satisfied. 
I  now  believe,  in  fact,  that  as  many  as  400  of  carrots  may  be  found 
requisite  to  replace  100  of  good  meadow-hay. 

The  carrot  crop  of  1841  having  been  a  failure,  I  had  to  limit  my- 
self to  observations  made  on  a  single  horse,  which  was  put  upon  a 
ration  in  which  11  lbs.  of  hay  were  replaced  by  38.5  lbs.  of  carrots 
The  horse,  habituated  to  this  diet, 

Weighed. 1025.2  lbs. 

A  fortnight  after 1014,2 

Loss  in  a  fortnight 11.0 

Nevertheless  he  remained  in  good  condition,  so  that  the  equivalent 
350  is  probably  not  far  from  the  truth.  I  ought  to  say,  however, 
that  the  men  think  this  number  too  low  ;  an  opinion  in  which  they 
would  be  borne  out,  could  we  but  be  certain  that  the  loss  of  weight 
of  the  horse  just  indicated  was  not  accidental. 
EXPERIMENT  X. 

BOILED  RYE  AS  A  SUBSTITUTE  FOR  OATS. 

It  has  been  stated,  that  rye  boiled  till  the  grain  bursts  may  be 
used  as  a  substitute  for  an  equal  bulk  of  oats  in  the  keep  of  a  horse. 
The  experiment  which  I  made  on  the  point  is  very  far  from  bearing 
out  any  thing  of  the  kind.  By  preliminary  trials  I  had  ascertained 
that  rye  of  good  quality  swells  to  twice  its  former  bulk  by  boiling. 

The  two  horses  that  were  made  the  subjects  of  experiment  now, 
had  been  kept  for  some  time  on  a  ration  formed  of : 

Hay 2.2  lbs. 

Oats 5.5        =8.8  pints. 

For  the  oats,  the  same  quantity  by  measure,  8.8  pints  of  boiled 
rye  were  substituted,  containing  4.4  pints  of  raw  grain,  weighing 
4.15  lbs.  On  the  Uth  day  it  was  deemed  prudent  to  interrupt  the 
experinient,  of  which  the  following  are  the  results  : 


406  MAINTENANCE   OF   ANIMALS. 

First  weighing :  Both  horses 2010  lbs.    Average  of  each 10045 

Second      "  "  1927  "  963.0 


Loss  in  11  days 83  41.5 

In  fact,  with  such  a  ration  as  this,  in  which  water  was  made  to 
replace  solid  corn,  no  other  result  could  reasonably  be  expected. 
In  continuing  it,  the  health  of  the  horses  would  very  certainly  have 
soon  been  seriously  compromised.  There  is  no  objection  to  rye  in 
Itself  as  an  element  in  the  food  of  a  horse  ;  but  then  it  must  be  sub- 
stituted in  the  quantity  indicated  by  the  table  of  equivalents,  by 
adopting  which,  Mr.  Dailly  found  that  he  could  keep  the  post-horses 
of  Paris  in  good  heart,  at  a  time  when  the  difference  between  the 
price  of  oats  and  rye  made  it  advantageous  to  substitute  the  latter 
for  the  for.rier.  The  experiments  of  Mr.  Dailly  on  the  subject  were 
so  decisive  and  so  ably  conducted,  that  I  felt  myself  relieved  from 
the  necessity  of  inquiring  further  into  it  myself. 

From  these  experiments,  the  particulars  of  which  have  now  been 
given,  it  may  be  conc'uded  that  the  nutritive  equivalents  of  the  po- 
tato, beet,  Jerusalem  potato,  and  carrot,  as  they  come  out  upon  ana- 
lysis, or  as  they  are  inferred  from  the  amount  of  azote  they  contain, 
may  be  adopted  without  detriment  to  the  health  of  horses.  If  they 
err  at  all,  it  is  that  they  assign  equivalents  somewhat  too  high, 
which  is  the  same  ay  saying  that  their  actual  nutritive  power  is 
rather  less  than  these  numbers  give  it ;  so  that  a  portion  of  the  hay 
of  the  standard  ration  being  substituted  for  its  equivalent  of  tuber  or 
root,  the  diet  will  be  improved. 

Thus,  100  of  good  meadow-hay  may  be  taken,  as  ascertained  by 
experiment,  to  be  equivalent  to  : 

280  potatcjs — ^by  analysis,  equal  to 315 

280  Jenisaiems 311 

400  beet 548 

400  Swede  (too  little) 676 

400  carrot  382 

In  the  following  table  of  nutritive  equivalents,  to  the  numbers  as- 
signed by  the  theory,  I  have  added  those  of  the  whole  which  I  find 
in  the  entire  Heries  of  observations  that  have  come  to  my  knowledge. 
I  have  also  given  the  standard  quantity  of  water,  and  the  quantity  of 
azote,  contained  in  each  species  of  food.  When  the  theoretical 
equivalents  do  not  differ  too  widely  from  those  supplied  by  direct 
observation,  I  believe  that  they  ought  to  be  preferred.  The  details 
of  my  experiments,  and  the  precautions  needful  in  entering  on  and 
carrying  them  through,  must  have  satisfied  every  one  of  the  difficul- 
ties attending  their  conduct ;  yet  all  allow  how  little  these  have  been 
attentively  contemplated,  and  what  slender  measures  of  precaution 
against  error  have  been  taken.  Our  equivalent  for  field-beet  is  400, 
a  number  come  to  by  introducing  44  lbs.  of  the  root  into  the  ration, 
in  lieu  of  11  lbs.  of  hay ;  had  we  introduced  56  lbs.,  the  equivalent 
number  would  have  come  out  500 ;  and  it  is  questionable  whether 
the  final  result  would  have  been  aflfected  by  this  substitution.  In 
my  o'pinion,  direct  observation  or  experiment  is  indispensable,  but 
mainly,  solely  as  a  means  of  checking  within  rather  wide  limits  tljp 
w?'}!^?  of  cheiflicjl  analysi?, 


MAINTENANCE  OF  ANIMALS. 


407 


Ordinary  natural  meadow-hay    . 
Ditto,  of  fine  quality     .... 

Ditto,  select           

Ditto,  freed  from  woody  stems    . 

Lucern  hay 

Red  clover.hay,  2d  year's  growth 
Red  clover  cut  in  flower,  green,  ditto 
New  wheat-straw,  crop  1841 

Old  wheat-straw 

Ditto,  ditto,  lower  parts  of  the  stalk  . 
Ditto,  ditto,  upper  part  of  ditto  and  ear 

New  rye-straw 

Old  ditto 

Oat-straw 

Barley  ditto           

Pea  ditto 

Millet  ditto 

Buckwheat  ditto           .... 

Lentil  ditto 

Vetches  cut  in  flower  and  dried  into  hay 

Potato  tops 

Field-beet  leaves 

Carrot  ditto 

Jerusalem  potato  stems        .       . 
Lime-tree  young  shoots 
Canada-poplar  ditto     .... 

Oak  ditto 

Acacia  ditto  (autumn) 

Drum  cabbage      

Swedish  turnip 

Turnip 

Field-beet  (1838) 

Ditto,  white  Silesian 

Carrots 

Jerusalem  potatoes  (18^)    . 

Ditto  C1836) 

Standard  water 
per  cent. 

Azote  per  cent. 

PPPPPPPP®.O.«.^.®P.®.®.^.-'PP.«P®P.OrP.<='PpH-WJ06S>-M. 

Azote  per  cent. 

in  the  article 

not  dried. 

^im^mB^BB^BBmn^m^mm^m^B^^^^^^ 

Theory. 

' '  mm-  g:  s^ 

ss:  ••  %•  •  W-  •  i^i 

:|: 

■•  ■■  ill: 

's 

"8 

Block. 

::g 

%^^W'  ■■ : 

:  :  :  :  ^^m^B^ 

§: 

:  :  §:  S5^ 

=  8 

=  8 

Petri. 

.'•g 

W-  W'  •  ' 

'  :  :  : 

:gss 

s* 

•:g::: 

=  8 

Meyer. 

::§ 

n§§^'  '  ' 

•:§: 

:iss 

1= 

•  : ||$8 

8 

Thaer. 

::| 

•  ^^§W-  ' 

:g:§ 

•m- 

•B§n 

'•&'• 

••  •  iisi 

8 

Pabst. 

nW'  %• '  • 

=  i^s 

'^' 

••'^W-' 

•i 

s 

Flottow. 

::§ 

-m''' 

'. 

ijg:  : 

: : :  g:  : 

8 

Pohl. 

••i 

■•ill::: 

.' 

•§ 

•s 

Rieder. 

:  =  ! 

liii:  ••  : 

s 

•gi 

§: 

'  8 

§ 

Gemerhausen. 

::| 

§¥¥'• 

:::§ 

8* 

'. '. '. 

88 

i 

Crud. 

'•^ 

:§:§::: 

:  :g 

•8 

Weber. 

'•'•m 

i^:  :  :  :  : : 

;  • 

■  8 

i 

Dombasle. 

'•'^ 

: 

:  :  ; 

=  8 

i 

Krantz. 

::i 

igi:::: 

;. 

•'  li- 

88 

8 

Schwertz. 

8 

s 

g£i 

ij 

:§ 

'8 

i 

Schnee. 

::S 

!i:::i: 

1     1      Midleton. 

!§;:i;: 

; 

.  ; 

1              Murre. 

•  l  ! 

::§!::: 

: 

'8 

g              Andr*. 

ill. 

§::;:!: 

®        Boussin^auh. 

408 


MAINTENANCE  OF  ANIMALS. 


Potatoes  (1838)       . 
Ditto  (1836)     . 
Ditto  after  keeping 
Cider  apple  pulpdr 
Beet-ro(jt  magma  f 
Vetciies  in  seed 
Field  beans 
Whire  peas  (dry) 
White  haricots 
I^entils     . 
New  maize     . 
Buckwheat     . 
Barley  (1836) 
Barley-meal 
Ditto 

Oats  (1838)      .       . 
Ditto  (1836)     . 
Ditto  (Parisian)     . 
Rye  (1836)      .       . 

Ditto  (1838) 

Ditto  from  highly  n 

Recent  bran  . 

Wheat  husks  or  ch 
Rice  (Piedmont) 
Gold  of  pleasure  se 
Ditto,  cake     . 
Linseed  cake  . 
Calza  ditto     . 
Madia  ditto    . 
Hemp  ditto 
Poppy  ditto 
Nut  ditto 
Beech  mast  ditto 
Arachis  (:•>)  ditto 
Dry  acorns 
Refuse  of  the  wine 

H 

H 

^ 

i".".'.::: 

in  the  pit 
ied  in  the  air 
rem  the  sugar 

aanured  soil 

aff.       . 
8d  (Madia) 

8. 3 

Standard  water 
per  cent- 

Azote  per  cent. 

.^pooeocnw4^o*.p.w.wrptar!*?o!*r«!*t-t-rrt-wr?=r'^'^ws"s«^ppppf 

s 

n 

<3 

s 

Azote  per  cent. 

ffifeSSSI2S2SBgKe£2^ig8RfcfeSg;Sgt3S8S22:gJS;Sgg?Kesii^Kl 

Theory. 

::;•.:: 

'  'fe 

•  •■  :  g:  g:  :  '  «:  &> 

'•  ss"  ' 

: : ggg* 

:i-'i 

Block. 

£2:  •. ;  :  : 

::s 

:::::::;: b: »: 

s: 

:  22§ 

s:  &s^f^ 

:::§ 

Petri. 

::::::: 

::::::::.'  j^:  g: 

;  ; 

•  a- 

'  '  feg: 

:::g 

Meyer. 

:  :  .'  : :  : 

:?::::::: g: 3: 

ag= 

•s=  • 

'•  'ass 

:::g 

Thaer. 

g:  : :  :  : 

::::::::  igig: 

8" 

■s'  • 

•  't^t 

:::| 

Pabst. 

•  •  1 1 . 1 1  •  • 

=  ife' 

:  : 

:::| 

Flottow.      1 

'.'.'.',','. 

: ! :  g: : : :  : 

'  88* 

S' 

'  '•  -sg: 

:::| 

Pohl.        1 

::::::. 

•b' 

8!  = 

•b" 

Rieder.       » 

::::::: 

:::::::::* 

:  :  :  : 

Gemerhausen. 

'.'.'.','.'. 

::::;:::: 

::i| 

Crud. 

::::::    .. s  ;:;:;:: ; 

Weber. 

•:::....; 

:::!:;.';: 

!^l 

*.'.•.§ 

Dombasle. 

1 : ; 

:::;;:'.:  \^\^\ 

!  i  ! 

;:..§ 

Krantz. 

;  ;  .  ;  :  i 

I  ',  ! 

!!!!!!!!! 

1  !  ! 

••'•■•8 

Schwertz. 

'  1  !  1  1 

: !  1 ;  i . ; : ; 

'B' 

Schnee. 

1 1    1 1  1  1  1  1 

••  1  1 



Midleton. 

::::;.';.; 

Murre. 

'.III!!!!; 

ig; 

1         AndrA. 

::!!: 

: ; : ; : : :  i ; 

S! 

: :  !] 

E!  !  :  ;  : 

!:!i 

Boussingault. 

MAINTErrANCE   OF   ANIMALS.  409 

To  complete  the  preceding  ample  table,  I  shall  still  add  the  equiv- 
alents of  a  few  articles  of  forage  that  have  not  yet  been  examined 
chemically. 

100  of  meadow-hay  are  replaced  by  : 

From  85  to  90  of  sainfoin  hay,  accor«iing  \o  Petri  and  Meyer. 

By  90  of  spurry  hay  "  Petri. 

325  to  500  of  green  spurry  "  Pabst  and  Flottow 

42  to  50  of  chestnuts  "  Block  and  Petri. 

By  50  of  Indian  chestnuts  "  Petri. 

62  of  turnsole  seeds  "  Petri. 

109  of  rye-bran  "  Bloclt. 

In  the  list  of  substances  there  are  some  which  are  used  almost 
exclusively  for  the  food  of  man,  and  I  have  thought  it  not  uninter- 
esting to  contrast  these  different  articles  with  reference  particularly 
to  the  quantity  of  azote  they  contain.  I  have  composed  the  follow- 
ing table  or  list  of  equivalents  on  this  basis;  ha\ing  assumed  wheat- 
en  flour  as  the  standard  and  called  it  100.  As  all  herbs,  roots, 
leaves,  &c.,  may  be  pulverized  after  drying,  I  hare  spoken  of  these 
articles  dry  under  the  name  of  meal. 

Wheat  flour  (good  quality) ...  100  White-heart  cabl  a  ge  810 

Wheat 107  Cabbage  meal 83 

Barley-meal 119  Potatoes 613 

Barley 130  Potato  meal 126 

Rye Ill  Carrots 757 

Buckwheat    108  Carrotmeal    95 

Maize 138  Turnips  1335 

Yellow  peas 67  Mealy  bananas  (Ficns  Indica)     700 

Horse-beans 44  Manihot  (casava  plart) 700 

White  French  beans 56  Name  "?  (discorea  saliva) 300 

Rice 171  Apiol  (arracacha)  .  1050 

Lentils    57 

Judging  from  the  equivalents,  leguminous  vegetables  must  be  pos- 
sessed of  a  much  higher  nutritive  value  than  wheat ;  and  it  is  known, 
indeed,  that  haricots,  peas,  and  beans,  form  in  some  sort  substitutes 
for  animal  food.  The  difference  indicated  is  so  great,  however,  that 
it  may  surprise  those  who  have  never  thought  of  the  subject  that 
engages  us.  In  a  general  way  we  are  all  perhaps  disposed  to  re- 
gard the  articles  that  enter  habitually  into  our  food  as  highly  nutri- 
tious. The  fact,  however,  is,  that  tubers,  roots,  and  even  the  seeds 
of  the  cereal  grasses  are  but  very  moderately  nutritious.  If  we  see 
herbivorous  animals  getting  fat  upon  such  things,  it  is  only  because 
their  organization  enables  them  to  consume  them  in  large  quantities. 
i  doubt  very  much  whether  a  man  doing  hard  work  could  support 
himself  on  bread  exclusively.  I  am  aware  that  countries  are  quoted 
where  the  potato  and  where  rice  form  the  sole  articles  of  food  of 
the  inhabitants ;  but  I  believe  also  that  these  instances  are  incom- 
plete. In  Alsace,  for  example,  the  peasantry  always  associate  their 
potato  diet  with  a  large  quantity  of  sour  or  curdled  milk  ;  in  Ireland 
with  buttermilk.  The  Indians  of  the  Upper  Andes  do  not  by  any 
means  live  on  potatoes  alone,  as  some  travellers  have  said  they  do ; 
at  Quito,  the  daily  food  of  the  inhabitants  is  lorco,  a  compound  of 
potatoes,  and  a  large  quantity  of  cheese.  Rice  is  often  cited  as  one 
of  the  most  nourishing  articles  of  diet ;  I  am  satisfied,  however,  af- 
ter having  lived  long  in  countries  where  rice  is  largely  consumed, 

35 


110  INORGANIC  ELEMENTS  OF  FOOD. 

that  it  is  any  thing  but  a  substantial,  or,  for  its  bulk,  nutritious  arti- 
cle of  sustenance.  This  is  an  important  question,  inasmuch  as  in 
some  departments  of  the  public  service  rice  is  sometimes  served 
out  as  a  substitute  for  other  articles  of  diet.  In  the  French  navy, 
for  example,  60  grammes,  or  about  20  dvi^ts.  of  rice  may  be  substi- 
tuted for  60  dwts.  of  split  peas  or  haricots  ;  but  I  cannot  hold  such 
a  substitution  to  be  either  fair  or  reasonable.  At  a  period  when  I 
had  myself  the  charge  of  the  rations  for  a  detachment  of  men,  I 
found  that  the  experience  of  the  country  where  I  was,  assigned  3 
lbs.  of  rice  as  the  equivalent  of  1  lb.  of  haricot  beans ;  and  analysis 
confirms  this  practical  conclusion. 

Haricots,  in  fact,  contain  about  0.046  of  azote  ;  rice  no  more  than 
0.014.  And  if  the  nutritious  properties  be  really  in  proportion  to 
the  amount  of  azote,  it  is  obvious  that  3|  of  rice  will  be  required  in 
lieu  of  1  of  the  leguminous  seed. 

We  hear  it  constantly  repeated  that  rice  is  the  sole  nutriment  of 
the  nations  of  the  whole  of  India.  But  the  fact  would  appear  not 
to  be  precisely  so  ;  and  I  may  here  quote  M.  Lequerri,  who,  during 
a  long  residence  in  India,  paid  particular  attention  to  the  manners 
and  customs  of  the  inhabitants  of  Pondicherri.  "  The  food,"  says 
M.  L.,  "  is  almost  entirely  vegetable,  and  rice  is  the  staple  ;  the  infe- 
rior castes  only  ever  eat  meat.  But  all  eat  kari,  an  article  prepared 
with  meat,  fish,  or  vegetables,  which  is  mixed  with  the  rice  boiled 
in  very  little  water.  It  is  requisite  to  have  seen  the  Indians  at  their 
meals  to  have  any  idea  of  the  enormous  quantity  of  rice  they  will 
put  into  their  stomachs.  No  European  could  cram  so  much  at  a 
time  ;  and  they  very  commonly  allow  that  rice  alone  will  not  nour- 
ish them.     They  very  generally  still  eat  a  quantity  of  bread."* 

^  II.    OF  THE  INORGANIC  CONSTITUENTS  OF  FOOD. 

We  discover  in  the  bodies  of  animals  the  several  mineral  sub- 
stances, the  existence  of  which  we  have  ascertained  in  vegetables. 
The  bones,  as  we  have  seen,  contain  a  large  quantity  of  phosphate 
of  lime  ;  it  is  requisite  therefore  that  the  elements  of  this  salt,  phos- 
phoric acid  and  lime,  should  form  part  of  the  ration  or  diet-roll ;  this 
is  a  point  upon  which  all  physiologists  are  agreed  ;  but  the  point 
upon  which  there  is  nothing  like  uniformity  yet  attained  h«.s  refer- 
ence to  the  precise  quantity  of  mineral  matter  which  must  enter  into 
the  constitution  of  the  food.  The  analyses  of  ashes  which  I  have  given 
show  that  if  vegetable  aliments  all  contain  nearly  the  same  inorganic 
principles,  they  still  contain  them  in  very  different  proportions  :  thus 
potatoes,  wheat,  oats,  and  beans,  contain  much  less  lime  than  clover, 
straw,  and  peas.  The  phosphoric  and  sulphuric  acids  and  the  alka- 
lies do  not  vary  less  ;  so  that  we  are  led  to  ask  whether  a  ration 
compounded  of  such  and  such  an  article,  or  of  such  and  such  arti- 
cles, will  furnish  the  animals  to  which  it  is  supplied  with  the  neces- 

*  The  Irish  peasantry,  who  live  so  much  on  potatoes,  have  buttermilk  with  them 
at  least,  often  salt  herring ;  and  a  laboring  man,  it  is  said,  will  consume  Ji  or  14  Iba 
per  diem !— £ho.  Eik 


INORGANIC  ELEMENTS  OF  FOOD.  411 

sary  dose  of  inorganic  principles,  which  must  be  assimilated  daily, 
and  which  is  quite  indispensable  to  maintain  them  in  health  and 
vigor. 

It  is  easy  to  arrive  at  a  knowledge  of  the  mineral  principles  which 
are  necessary  as  elements  of  the  diet,  by  ascertaining  their  quantity 
in  the  ration,  which  long  experience  has  shown  to  be  sufficient.  Yet 
as  there  is  reason  to  believe  that  in  many  cases  mineral  substances 
are  present  in  excess,  I  have  thought  that  it  might  be  useful  to  de- 
teimine  by  means  of  analysis  the  nature  and  the  proportion  of  the 
inorganic  elements  which  are  actually  assimilated  by  .an  individual, 
in  order  to  have  a  minimum  which  might  serve  as  a  basis  for  any 
reasonings  or  inferences  on  the  subject.  My  experiments  were  per- 
formed in  two  opposite  circumstances  in  which  I  regard  assimilation 
as  most  rapid  and  most  complete  :  videlicit,  a  calf  in  full  growth, 
and  a  milch-cow  in  calf 

The  calf  was  six  months  old,  and  weighed  369  lbs.     Some  days 

before  being  made  the  subject  of  experiment  it  was  fed  with  hay. 

During  the  two  days  when  it  had  this  fodder  ad  libitum,  it  ate  19  lbs. 

In  the  course  of  the  1st  day  the  calf  passed  21.49  lbs.  of  excrements. 
2d  day  "        20.39    "  " 

41.88 

Which,  dried,  was  reduced  to  7.41  lbs. 

In  the  course  of  the  two  days  5.584  lbs.  of  urine  were  collected, 
which,  evaporated,  yielded  2933.2  grains  of  extract,  the  animal  hav- 
ing in  the  same  interval  drunk  45.7  pints  of  water. 

Analysis  discovered  in  100  : 

Of  the  hay Azote  1.6  Ashes  7.6 

Of  the  dry  excrements "2.1  "    12.7 

Of  the  urinous  extract "      4.0  "    40.0 

Now  if  we  inquire  from  these  data  in  regard  to  the  quantity  o' 
azote  and  of  mineral  matters  which  were  assumed  with  the  food  in 
the  course  of  two  days,  we  have  : 

half-drachms.  half-drachmi. 

In  the  food,  discarding  fractions,  Azote  69      Mineral  substances  328 
In  the  excrements       "  "50.5  "  214 

In  the  urine  "  "       3-8  "  38 

Together       54.3  252 

Therefore,  azote  fixed  or  exhaled  in  2  days  14-7  half-drachms. 
Mineral  substances  fixed  in  2  days 76  " 

The  composition  of  the  ashes  obtained  from  the  hay  and  from  the 
excrements,  shows  us  approximatively  both  the  quantity  and  the 
nature  of  the  several  inorganic  substances  which  had  been  assimi- 
lated     The  composition  of  these  ashes  is  as  follows : 

Of  the  bay.  Of  the  excrements.  Of  the  urine. 

(Carbonic 9.0  2.0  17.3 

Acids     <  Phosphoric 5.3  5.1  0.2 

(Sulphuric 2.4  2.3  7.0 

Chlorine 2.3  1.9  9.9 

Lime 20.4  16.0  0.9 

Magnesia 6.0  6.5  6.0 

Potash  and  soda 17.3  12.5  57.3 

Oxide  of  iron,  alumina 1.5  1.0  " 

Wlesia 33.7  51.0  1.9 

LoM 2.1  1.7 

100.0  100.0  IjOOuO 


412  INORGANIC    ELE3IENTS    OF    FOOD. 

if  the  hay  consumed  contained  328  half-drachms  of  ash  or  mineral 
matter,  the  excrements  and  urine  252  half-drachms  of  the  same 
matters ;  the  difference  between  the  two  sums,  76  half-drachms,* 
is  the  quantity  of  mineral  matter  fixed  in  the  course  of  two  days,  of 
which  200.6  grains  were  phosphoric  acid,  and  494.0  grains  were 
lime.  This  quantity  of  lime,  however,  is  more  than  four  times  as 
much  as  is  necessary  to  constitute  a  subphosphate  of  lime  such  as 
exists  in  the  bones.  It  is  true,  indeed,  that  there  is  always  a  quan- 
tity of  carbonate  of  lime  associated  with  the  subphosphate  in  bones ; 
10  of  carbonate  for  38  of  phosphate,  according  to  Fourcroy  and 
Vauquelin,  in  those  of  the  ox.  Still  the  quantity  of  lime  assimilated 
was  vastly  more  than  it  ought  to  have  been,  had  it  only  gone  to  assist 
in  the  formation  of  bone.  If  there  was  no  error  in  the  observations, 
it  is  probable  that  the  base  in  question  enters  into  the  constitution  of 
the  salts  with  organic  acids  which  are  encountered  in  all  parts  of 
the  animal  body. 

By  a  series  of  weighings,  I  ascertained  that  my  calf,  fed  simply 
upon  hay,  increased  every  day  by  a  quantity  equal  to  9725.9  grains 
troy,  in  which  were  included  858.35  grains  of  mineral  substances, 
the  calcareous  phosphate  and  carbonate  of  the  bones  in  this  quan- 
tity being  represented  by  262.4  grains,  or  nearly  3  per  cent,  of  the 
entire  weight  acquired  in  the  course  of  twenty-four  hours.  ' 

In  the  experiment  with  the  milch-cow  in  calf,  I  limited  my  inqui- 
ries to  the  phosphoric  acid  and  the  lime  taken  in  and  given  out. 
The  animal,  four  years  old,  was  '2^  months  gone  with  calf,  and 
weighed  1452.6  lbs.  She  had  the  same  allowance  during  the  expe 
riment  as  she  had  had  for  several  days  before,  and  which  for  twenty 
four  hours  consisted  of — 

Ha3- 16.5  lbs. 

Cut  wheat-straw.  •••  9.9 
Beet 59.4 

The  experiment  was  continued  for  four  days,  during  which  tho 
excrements,  the  urine,  and  the  milk,  were  carefully  collected  and 
weighed,  and  the  ashes,  both  of  the  food  consumed  and  of  the  pro- 
ducts rendered,  were  determined  by  chemical  analysis.  Suffice  it  to 
say,  that,  representing  the  quantity  of  mineral  matters  assumed  into 
the  body  in  the  course  of  the  experiment  by  849.9  half-drachms,  the 
quantity  voided  amounted  to  no  more  than  556  half-drachms.  In  the 
quantity  assumed,  there  were  100.2  half-drachmsof  phosphoric  acid, 
and  203.8  half-drachms  of  lime ;  in  the  quantity  voided,  there  were 
but  68.2  half-drachms  of  phosphoric  acid,  and  116.8  half-drachms 
of  lime  :  this  is  at  the  rate  of  about  8  half-drachms  of  phosphoric 
acid,  and  22  half-drachms  of  lime  assimilated  in  the  course  of  twenty- 
four  hours.  Here,  as  in  the  case  of  the  calf,  the  quantity  of  lime 
assimilated  is  greatly  superior  to  what  it  ought  to  be,  in  order,  by 
combining  with  the  phosphoric  acid,  to  constitute  the  phosphate  of 
lime  of  the  bones. 

From  these  inquiries  into  the  nutrition  of  a  calf  and  of  a  cow  in 

•  The  szact  quantity  is  2392.8.grain8  troy.— Ema.  E». 


INOBGANIC    ELEMENTS    OF   FOOD.  413 

calf,  it  follows  that  tnere  is  a  portion  of  the  mineral  substance  taker 
in  with  the  food,  which  remains  definitively  fixed  to  concur  in  the 
growth  or  in  the  evolution  of  the  individual.  In  an  adult  animal  it 
is  to  be  presumed  that  no  such  definitive  fixation  of  inorganic  prin- 
ciples takes  place,  or  that  it  is  much  less  considerable ;  that  in  the 
dejections  and  several  secretions  ought  to  be  found  the  whole  of  the 
phosphoric  acid,  of  the  lime,  &c.,  taken  in  with  the  food.  And  this 
presumption  is  confirmed  by  experience  ;  for  on  instituting  an  inquiry 
into  the  matter  upon  a  horse,  it  was  found  that  the  mineral  matters 
assumed  were  almost  exactly  balanced  by  those  discharged.  Never- 
theless, and  granting  this  to  be  quite  true,  which  it  is,  it  would  be  a 
grave  mistake  to  suppose  that  an  adult  animal  could  go  on  for  even 
a  very  short  period  of  time  upon  food  that  contained  no  mineral 
matter.  Precisely  as  in  the  case  of  organic  matter,  it  appears  that 
a  portion  of  inorganic  matter  is  also  fixed  in  the  living  frame,  where 
for  a  time  it  forms  an  integral  element  in  the  wonderful  structure  ; 
and  a  supply  of  the  latter  kind  is  undoubtedly  no  less  necessary  than 
is  the  supply  of  the  former  description  recognised  by  all  the  world. 
Were  there  an  inadequate  quantity  of  phosphoric  acid,  of  lime,  &c., 
in  the  food,  no  question  but  that  the  body  would  speedily  feel  the 
effects  of  the  deficiency,  and  that  disease  and  death  would  by  and  by 
put  an  end  to  life.  So  much,  indeed,  seems  demonstrated  by  thi> 
very  interesting  experiments  of  M.  Chossat,  in  which  he  kept 
granivorous  animals  upon  a  diet  rich  in  azotized  principles  and  in 
starch,  but  deficient  in  lime.  From  some  previous  inquiries,  M. 
Chossat  had  observed  that  pigeons  even  require  to  add  a  certain 
proportion  of  lime  to  their  ordinary  food,  the  quantity  naturally  con- 
tained in  which  does  not  suffice  them.  Wheat,  as  we  have  seen, 
though  it  contains  a  large  proportion  of  phosphate  of  magnesia,  con- 
tains very  little  phosphate  of  lime ;  and  pigeons  put  on  this  grain, 
though  they  do  perfectly  well  at  first,  and  even  get  fat,  begin  by  and 
by  to  fall  oflf.  In  from  two  to  three  months,  the  birds  appeared  to 
suffer  from  constant  thirst ;  they  drank  frequently  ;  the  fceces  be- 
came soft  and  liquid,  and  the  flesh  wasted,  and  in  from  eight  to  ten 
months  the  creatures  died  under  the  effects  of  a  diarrhoea,  which 
M.  Chossat  attributed  to  deficiency  of  the  calcareous  element  in  the 
food.  And  it  is  neither  uninteresting  nor  unimportant  to  observe, 
that  the  same  thing  occasionally  occurs  in  the  human  subject  during 
the  period  when  the  process  of  ossification  is  usually  most  active. 
But  one  of  the  most  remarkable  features  of  M.  Chossat's  experi- 
ments was  observed  in  the  state  of  the  bones  of  the  pigeons ;  they 
became  so  thin  and  weak  that  they  broke  during  the  life  of  the  birds 
with  the  slightest  force.*  The  conclusion  from  this  fact  is  obvious. 
Supplies  of  all  the  elements  of  all  the  parts  of  the  body  are  indispen- 
sable to  the  maintenance  of  health,  to  the  continuance  of  life. 

A  pigeon  will  eat  about  463.140  grains  of  wheat  per  diem,  con- 
taining 9.725  grains  of  ash,  in  which  analysis  discovers  4.569  grains 
of  phosphoric  acid,  and  0.277  of  a  grain  of  lime.     But  this  smaU 

*  Chossat,  in  Comptes  Rendiis,  t.  xiv.,  p,  451. 
35* 


414  INORGANIC  ELEMENTS  OF  FOOD. 

quantity  of  lime  is  incompetent  to  maintain  the  bones  in  their  stan- 
dard condition.  I  have  thought  it  of  moment  to  insist  upon  these 
facts,  because  I  see  that  they  may  sometimes  come  into  play  in  practi- 
cal rural  economy.  No  breeder  or  feeder  ought  to  be  ignorant  of 
the  influence  of  mineral  substances  on  nutrition.  It  is  not  only  indis- 
oensable  that  the  allowance  of  an  animal  in  full  growth  be  sufficient 
to  support,  and  even  to  add  to  the  soft  textures  ;  it  must  further  con- 
tain the  elements  requisite  for  the  nutrition  of  the  osseous  system  : 
and  it  is  not  impossible  but  that,  in  managing  the  feeding  of  young 
cattle  or  young  horses  in  such  a  way  as  to  reduce  to  a  minimum,  or 
to  give  in  excess,  certain  of  the  inorganic  elements  of  the  food,  we 
may  succeed  in  impressing  one  character  or  another  upon  a  race. 
It  is  even  possible  that  the  empirical  rules  which  are  acted  upon 
with  a  view  to  increase  or  diminish  the  quantity  of  bone,  the  weight 
of  flesh  or  of  fat,  &c.,  are  all  connected  with  various  proportions 
of  phosphoric  acid,  of  lime,  magnesia,  &c.,  in  the  food.  It  will 
probably  be  discovered,  some  day,  that  Bakewell's  art  is  to  be  ex- 
plained through  the  composition  of  the  ashes  of  the  food. 

Wheat  is  not  the  only  alimentary  matter  that  contains  an  insuf- 
ficient quantity  of  lime ;  maize  or  Indian  corn  contains  still  less . 
and  if  that  which  is  grown  in  the  tropics  contains  as  little  as  that 
which  is  produced  in  Europe,  it  would  be  difficult  to  explain  how 
the  grain  should  answer  so  well  as  it  unquestionably  does  for  food.* 
It  is  true  that  it  is  seldom  or  never  consumed  alone  and  without 
addition  ;  and  in  South  America,  where  the  animals  have  it  largely, 
I  have  observed  that  they  frequently  eat  earth.  The  habit  which 
certain  tribes  of  the  natives  have  of  eating  earth,  too,  which  has 
been  particularly  remarked  upon  by  travellers  and  missionaries  as  an 
instance  of  depravation  of  taste,  presents  itself  to  me  in  quite  another 
light,  since  1  became  acquainted  with  the  composition  of  the  ashes 
of  the  ordinary  article  of  diet  in  the  countries  where  it  occurs.f 

The  calcareous  and  other  salts  necessary  to  nutrition,  how- 
ever, are  not  derived  from  the  food  exclusively  ;  the  water  that  is 
generally  consumed  contains  a  quantity  which  is  by  no  means  to  be 
neglected.  A  horse  or  a  cow,  for  instance,  which  drinks  from  15 
to  45  quarts  of  water  per  diem,  will  even,  if  the  water  be  as  pure  as 
that  of  the  Artesian  well  of  Grenelle,  take  in  from  35  to  108  grains 
of  saline  matter  in  which  carbonate  of  lime  predominates  ;  water  that 
is  less  free  from  saline  impregnation  would  of  course  introduce  a 
much  larger  proportion  ;  some  waters  in  the  quantities  above  speci- 
fied will  contain  from  138  to  upwards  of  400  grains  of  saline  matter, 
one  half  of  which  may  be  carbonate  of  lime.  And  I  am  here  speak- 
ing of  clear  or  filtered  water  ;  that  which  is  muddy  or  turbid  con- 
tains a  still  larger  quantity  of  earthy  matter  in  suspension  than  in 
solution.  In  an  experiment  made  for  the  purpose  of  getting  at  the 
amount  of  earthy  matter  taken  by  a  milch-cow  from  the  watering- 

♦  An  ash  of  maize,  analyzed  in  my  laboratory  by  M.  LetelJier,  contained  bat  1.3  pel 
•ent.  of  lime  to  50.1  of  phosphoric  acid  and  17.0  of  magnesia. 

1 1  several  times  saw  children  chastised  in  Indian  villages  who  h«d  been  saufk 
•ating  earth. 


INORGANIC  ELEMENTS  OF  FOOD. 


415 


trough  in  the  course  of  the  day,  I  found  that  it  amounted  to  about 
770  grains  troy. 

Notwithstanding  these  facts,  it  is  still  doubtful  whether  the  lime 
contained  in  ordinary  well-water  would  prove  sufficient  to  supply  a 
growing  animal  with  the  material  requisite  to  the  formation  of  its 
bones  ;  in  adults,  indeed,  changes  in  the  elements  of  the  bones  ap- 
pear to  proceed  so  slowly  that  a  very  small  quantity  of  calcareous 
matter  probably  suffices  to  repair  losses  ;  but  it  is  otherwise  with 
young  and  growing  animals.  I  have  shown  that  a  calf  six  months 
old  receives  with  its  forage  a  quantity  of  phosphoric  acid  which  cor- 
responds to  555.7  grains  of  phosphate  of  lime.  A  calf  a  few  weeks 
old,  when  it  has  17  or  18  pints  of  milk  per  diem,  receives  802.7 
grains  of  mineral  substances,  into  which  subphosphate  of  lime  or 
bone  earth  enters  in  the  proportion  ot  370.5  grains.  It  would  be  in- 
teresting to  ascertain  what  quantities  of  these  substances  were  as- 
similated by  so  young  an  animal,  and  at  a  period  when  the  growth 
is  so  rapid  that  the  increase  from  day  to  day  sometimes  exceeds  2 
pounds. 

The  importance  of  the  inorganic  principles  of  the  food  once  re- 
cognised, it  concerns  us  to  take  note  of  their  nature  and  quantity  in 
the  ratio  we  allow  to  our  domestic  animals.  It  is  in  fact  this  con- 
sideration which  has  led  me  to  determine  the  quantities  of  phospho- 
ric acid  and  lime  contained  in  the  various  articles  of  food  the  ashes 
of  which  have  been  analyzed.  With  these  data  the  proportion  of 
bone  earth  contained  in  a  given  ration  is  forthwith  perceived. 

One  thousand  parts  of  the  forage  gathered  at  Bechelbronn  in  its 
ordinary  state  contained  : 


Forage. 


Hay 

Potatoes 

Beet 

Turnip ■ 

Jerusalem  Potato 

Wheat 

Maize 

Oats 

Wheat-straw  •  •  •  < 

Oat-straw 

Clover-hay 

Peas 

Haricots 


Mineral  *„„,.       Phospho-        ,  -^^  Bone 

Substance*.       ^^°*-^'       ric  icid.        ^"°«'  earth. 


62.33 
9.64 
7.70 
5.70 
12.47 
20.51 
11.00 
31.74 
51.90 
35.70 
73.50 
30.00 
3500 
30.00 


11.50 

3.70 

2.10 

1.30 

3.75 

20.50 

16.40 

17.87 

3.00 

300 

21.00 

38.40 

45.80 

51.10 


3.37 
109 
0.46 
035 
1.35 
9.64 
5.51 
4.73 
1.61 
1.07 
4.63 
9.03 
9.38 
10.26 


10.04 
0.17 
0.54 
0.62 
029 
0.60 
0.14 
1.17 
441 
2.97 

18.08 
3.03 
2.03 
1.53 


0.33 
0.95 
0.72 
0.56 
1.16 
0.27 
2.27 
3.32 
2.21 
9.85 
5.83 
5.94 
9.27 


We  seem  here  to  observe  a  certain  relation  between  the  proportion 
of  azote  ard  that  of  the  phosphoric  acid  contained  in  the  food ;  the 
most  highly  azotized  are  also  those  that  generally  contain  the  largest 
quantity  of  the  acid,  a  circumstance  which  seems  to  indicate  that  in 
the  vegetable  kingdom  the  phosphates  are  connected  more  especially 
with  the  azotized  principles,  and  that  they  accompany  them  in  pass- 
ing into  the  textures  of  animals.  With  the  assistance  of  the  above 
table  it  is  easy  to  ascertain  the  quantity  of  phosphate  of  lime  which 


416 


FATTY  ELEMENTS  OF  FOOD,  AND  ON  FAITENING. 


enters  into  a  given  ration.  Let  us  take  that  given  to  the  horse?  in 
experiment  3d,  in  which  the  half  of  the  hay  was  replac-'id  by  pot\- 
4X)es,  one  of  the  articles  that  contains  the  smallest  proportion  of  liu«*J, 
and  we  find  in  the 

26.6  lbs.  of  hay       632.9  grs.  phosphoric  acid  and  1867.9  grs.  of  liire. 
30.8  lbs.  potatoes    387.7  "  37.0 


1020.6 


1904.9 


numbers  which  correspond  with   1798.5  grains  of  bone  earth,  \' 
078.7  grains  of  uncombined  lime. 

In  his  usual  allowance  a  work-horse  at  Bechelbronn  receives  : 

Hay      22  lbs.  containing  524.8  grs.  phosphoric  acid,  and  1543.8  grs.  of  lime. 

Straw  5.5  "  60.7 

Oats     7.2  "  230.2  " 


81.57 

In  other  words,  1735  grains  of  bone  earth,  and  864  grains  of  fret 
lime. 

I  have  found  that  very  young  foals,  growing  rapidly,  and  weigh 
ing  about  374  lbs.,  consume  per  diem  : 

'-«-«        Hay-  ■ .  •  J9.8  lbs.  containing  of  phosphoric  acid  463  grs. :  lime  1389  grs. 
Oats...  75  "  "  231        "  58.6 

which  represent  95  of  bone  earth  or  subphosphate  of  lime.  As  a 
consequence  of  the  relation  which  appears  to  exist  between  the 
azote  and  phosphoric  acid  of  an  article  of  sustenance,  it  comes  to 
pass  that  like  nutritive  equivalents  also  indicate  like  proportions  of 
phosphoric  acid  ;  so  that  by  introducing  a  suitable  quantity  of  hay  or 
clover,  articles  that  abound  in  lime,  into  the  ration,  we  are  always 
certain  of  having  food  favorable  to  the  development  of  the  osseous 
system,  whatever  the  nature  and  quality  of  the  other  articles  that 
enter  into  the  constitution  of  the  allowance. 

The  relation  of  the  phosphoric  acid  to  the  azote  approaches  the 
ratio  of  3  to  10.  in  the  more  ordinary  articles  of  forage  ;  but  the 
same  relation  is  no  longer  apparent  in  the  cereals  and  leguminous 
vegetables  ;  in  grain  and  in  peas,  beans,  &c.,  the  phosphoric  acid 
amounts  to  about  a  fourth  of  the  azote  contained.     Thus  we  have  : 


Theoretical 
equivalent. 


100 


Hay 

Potatoes 320 

Beet 548 

Turnip 885 

Jerusalems  273 

Dry  clover 75 

Wheat-straw...  235 


Phosphoric 
acid  in  the 
equiralent. 

0.34 

0.35 

0.28 

0.31 

0.37 

0.S4 

0.37 


Theoretical 
equivalent. 

Oat-straw 380 

Oats 68 

Maize 70 

Wheat 43 

Peas 25 

Haricots 27 

Beans 23 


Phoiphone 
acid  in  the 
equivalent. 

0.40 

0.32 

0.38 

0.41 

0.23 

0.25 

0.24 


^  in.    OF  THE  FATTY  CONSTITUENTS  OF  FORAGE  :    CONSIDERATIONS    ON 
FATTENING. 

When  fat  was  observed  accumulating  in  the  tissues  of  the  animal 
body,  and  it  was  unknown  that  the  presence  of  fatty  matters  in 
plants  is  what  may  be  termed  a  general  fact,  men  naturally  con- 
ceived that  the  fat  was  produced  from  the  food  in  the  act  of  dige» 


FATTY  ELEMENTS  OF  FOOD,  AND  ON  FATTENING.  '117 

tion,  that  it  was  composed  in  the  animal  body  much  in  the  same  way 
as  it  is  formed  in  the  seed  and  leaf  of  the  living  vegetable. 

The  inquiries  which  I  am  about  to  present,  however,  all  tend  to 
make  us  conclude  that  fatty  substances  are  only  produced  in  vege- 
tables, and  that  they  pass  ready  formed  into  the  bodies  of  animals, 
where  they  may  either  undergo  combustion  immediately,  so  as  to 
evolve  the  heat  which  the  animal  requires,  or  be  stored  up  in  the 
tissues  in  order  to  serve  as  a  magazine  of  combustible  matter. 

This  latter  view  appears  the  most  simple  ;  but  before  discussing 
the  experiments  which  bear  it  out,  it  seems  necessary  to  pass  in 
brief  review  the  notions  that  have  been  entertained  at  different  times 
on  the  formation  of  fat.  When  the  great  burying-place  of  the  In- 
nocents was  emptied,  for  example,  it  was  commonly  imagined  that 
one  of  the  effects  of  the  putrefactive  process  was  to  convert  the 
flesh,  the  brain,  the  viscera,  &c.,  into  fat — adipocire,  as  it  was 
called  ;  it  was  not,  indeed,  till  after  the  researches  of  M.  Chevreul 
had  been  undertaken,  and  that  it  was  discovered  adipocire  contained 
the  same  acids  as  human  fat,  which  had,  in  fact,  only  been  partially 
saponified  by  ammonia, — until  the  inquiries  of  M.  Gay-Lussac  were 
made  public — that  it  was  acknowledged  that  muscular  flesh  or  fibrine 
subjected  to  putrefaction  leaves  no  larger  a  quantity  of  fat  than  can 
be  obtained  from  it  by  proper  solvents  before  it  has  undergone  any 
change  :  the  effect  of  putrefaction  is  to  destroy  the  fibrine,  and  so  to 
expose  the  fatty  substance  which  it  contained. 

It  may  therefore  be  said,  that  all  these  fortuitous  opinions  upon 
the  supposed  formation  of  fat  by  chemical  processes,  have  vanished 
as  they  have  been  successively  subjected  to  careful  examination. 

Let  us  now  turn  to  the  inferences  come  to  by  physiology.  The 
Dodies  of  carnivorous  animals  are  often  loaded  with  fat ;  and  none 
can  be  detected  in  any  of  their  excretions.  It  is  therefore  in  these 
animals  that  it  must  be  most  easy  to  ascertain  the  source  or  origin, 
and  mode  of  disappearance  of  fatty  matter. 

When  the  progress  of  digestion  is  watched  in  a  dog,  it  is  soon 
discovered  that  the  chyle  is  far  from  being  a  fluid  having  uniformly 
the  same  characters  and  qualities.  That  which  is  produced  under 
the  influence  of  a  vegetable  diet,  abounding  in  the  starchy  principle 
and  in  sugar,  or  after  a  meal  of  perfectly  lean  meat,  is  always  and 
alike  poor  in  molecules  or  globules.  The  chyle  is  then  nearly  trans- 
parent, extremely  serous,  and  yields  very  little  fat  when  washed  with 
ether.  But  if  the  animal  have  a  meal  of  fat  food,  the  chyle  that  re- 
sults from  it  is  opaque  like  cream,  very  rich  in  particles,  and,  digest- 
ed with  ether,  yields  a  large  quantity  of  fatty  or  oily  matter  to  that 
solvent. 

These  facts,  observed  by  M.  Magendie,  and  confirmed  with  more 
ample  details  by  Messrs.  Sandras  and  Bouchardat,  show  that  the 
fatty  principles  of  our  food  minutely  subdivided  or  made  into  an 
emulsion  by  the  act  of  digestion,  pass  without  undergoing  any  es- 
sential change  into  the  chyle,  and  from  that  into  the  blood,  whithei 
they  can  in  fact  be  followed,  and  in  which  they  can  be  shown  tc 
remain  for  a  longer  or  a  shorter  time  unaltered,  at  the  disposal  of 


418  FATTY  ELEMENTS  OF  FOOD,  AND  ON  FATTENING. 

the  economy,  as  it  were.  Such  observations  have  naturally  led 
physiologists  to  conclude  that  the  fatty  principles  of  the  food  were 
the  principal,  if  not  the  only  sources  whence  animals  derive  the  fat 
which  is  met  with  stored  up  in  their  tissues,  or  which  appears  in  the 
butter  of  their  milk.  And  this  view,  so  long  as  the  carnivorous 
tribes  alone  are  considered,  has  not  a  single  feature  which  makes  it 
objectionable.  But  when  we  would  extend  it  to  the  herbivorous 
tribes,  two  difficulties  meet  us  on  the  threshold  of  the  inquiry. 

1st.  Do  vegetables  actually  contain  such  a  quantity  of  fatty  matter 
in  their  structure  as  will  explain  the  fattening  of  cattle  and  the  for- 
mation of  milk  1 

2d.  Is  it  not  more  simple  to  suppose  fat  and  butter  the  product  of 
certain  transformations  undergone  by  starch  and  sugar  in  the  animal 
economy  1 

It  appears  at  first  sight  most  opposite  to  nature  to  suppose  that  the 
feeding  ox  finds  the  whole  of  the  fat  he  lays  on  ready  formed  in  the 
food  he  eats  ;  it  is  only,  in  fact,  after  having  made  repeated  analyses 
of  plants,  and  discovered  fatty  matters  almost  everywhere,  and  in 
quantities  generally  superior  to  any  that  had  been  suspected  in  the 
composition  of  plants,  that  the  idea  begins  to  acquire  likelihood ; 
finally,  the  chemist  becomes  convinced  that  it  is  so  when  he  finds  a 
regular  association  of  neutral  azotized  substances  and  fatty  principles 
in  all  the  articles  usually  employed  as  food  for  cattle, — in  the  grass- 
es and  cereals,  in  the  leaves  and  stems  and  seeds  of  plants. 

Fatty  substances  appear  to  be  principally  formed  in  the  leaves, 
where  they  frequently  show  themselves  under  the  form  and  with 
the  properties  of  wax.  Taken  into  the  bodies  of  animals,  mingled 
with  the  blood,  and  exposed  to  the  influence  of  the  oxygen  of  the 
inspired  air,  they  will  undergo  an  incipient  oxidation,  whence  will 
result  the  stearic  or  oleic  acid  that  is  found  as  a  constituent  of  suet. 
By  undergoing  a  second  elaboration  in  the  bodies  of  the  carnivora, 
the  same  fatty  substances,  oxidated  anew,  would  produce  the  mar- 
garic  acid  which  characterizes  their  fat.  These  divers  principles, 
by  a  still  further  degree  of  oxidation,  would  give  rise  to  the  fat  vola- 
tile acids  which  make  their  appearance  in  the  blood  and  in  the  per- 
spiration. Finally,  did  they  suffer  complete  oxidation,  i.  e.  combus- 
tion, they  would  be  changed  into  carbonic  acid  and  water,  and  be  in 
this  shape  eliminated  from  the  economy. 

Among  the  various  properties  possessed  by  fatty  substances,  there 
is  one  which  may  play  an  important  part  in  the  phenomena  of  fatten- 
ing ;  this  is  the  solvent  power  which  they  severally  possess  in  re- 
gard to  one  another  ;  the  property  of  mixing  in  all  imaginable  pro- 
portions, still  preserving  the  general  features  which  severally  dis- 
tinguish them.  In  the  stomach,  in  the  intestines,  in  the  chyle,  and 
in  the  blood,  fatty  substances  of  various  kinds  may  form  homoge- 
neous matters  by  their  intimate  admixture,  and  become  divided  into 
globules  of  complex  composition,  but  everywhere  the  same. 

Another  property  of  fatty  matters  of  every  kind,  which  deserves 
particular  attention,  is  that  of  insolubility  in  water.  We  find,  in 
fact,  that  when  an  animal  eats  a  soluble  substance,  that  in  general  il 


FATTY  ELEME:XTS  OF  FOOD,  AKD  OH  FATTEJIiXO.  419 

i»  cob^nmed  by  a  true  process  of  combastion,  which  conrcrto  iU 
-jarbDQ  into  carbonic  acid,  and  its  hydrogen  into  water ;  or  otherwise, 
•X  13  simply  eliminated  without  change  in  the  nrine. 

Fatty  matters  may,  indeed,  disappear  under  the  first  form ;  bat 
%o  long  as  they  escape  remarkaUe  modification,  it  is  certain  tint 
ihey  do  not  pass  off  by  the  urine,  and  that  the  quantity  eliminated 
by  the  perspiration  is  insignificant.  Their  ins^ubilitj,  therefore. 
retains  them  in  the  economy  once  they  have  eotered  tftie  blood  or 
the  tissues ;  and  it  is  in  virtue  of  this  quality  that  tiiej  cuaBlilole  a 
kind  of  mmgaxine  of  combustible  matter  in  the  umnl  body.  TUo 
18  the  principal  reason  wherefore  individuala  eapiilied  with  food  mi 
excess  get  fat,  and  that  those  insufficiently  fed  fiill  leas ;  the  httj 
matter  being  deposited  in  the  interstices  of  the  tiawca  ia  the  foimr 
case,  being  taken  up  from  tbem  and  buned  m  the  aeoood. 

This  explanation  is  anractively  simple  ;  bat  ia  oar  attachment  to 
it  we  must  not  forget  that  other  expiaaatiooe  hare  also  been  giren  : 
and  in  particular  it  must  be  contiaMed  with  a  view  which  has  been 
formed  upon  certain  inquiries  undertaken  by  M.  Dumas.  It  is 
known,  for  instance,  that  sugar  may  be  regarded  as  a  eonpoaad  of 
carbonic  acid,  water,  and  olefiant  gas.  Now  there  is  nnthiag  to  pie- 
vent  olefiant  gas  becoming  d^aehed  sad  takia^  diicieait  states  of 
condensation,  to  give  rise  to  bodies  whieh  by  onderg ois^  oiidstina 
would  produce  fat  acids  and  consequently  fats.  Since  it  has  beea 
known  that  the  oil  ofpot^ito  spirit  is  also  met  with  in  the  spint  obtaia- 
ed  from  the  refuse  of  the  grape,  and  ia  the  spint  ptocaiod  finaa 
malt,  and  from  the  molasses  of  beeuroot  sagar,  the  assorsace  that 
the  oil  is  a  product  ef  the  fermenution  of  sogar  ipposrs  to  be  com- 
plete. 

We  ought  even  to  be  prepared  to  admit  a  pheoomen<»i  of  the  same 
kind  as  ta^ng  place  in  plants,  when  we  see  the  sugar  of  their  stems 
disappearing  in  the  same  ratio  as  their  seeds  or  fiwts  bee  Mas  charg- 
ed with  oleaginous  matter :  all  the  palms  elabMate  si^ar  hefoia 
producing  oil. 

It  is  upon  chemical  views  of  this  kind  that  the  socoad  opskai  as 
to  the  source  of  fat  in  animals  has  been  formed,  sod  whieh  may  he 
said  to  stand  in  direct  contrast  with  that  which  assumes  this  sub- 
stance as  pre-existing  in  the  food,  which  regards  it  as  prodnced  in 
the  blood  itself,  under  the  influences  of  the  most  intimate  fagcoo  of 
animal  life.  For  my  own  part,  I  adopt  the  view  which  lajiiiooes  sa 
animal  to  be  supplied  with  fait  alresidy  formed,  BMiafy  ^miw  it 
presents  itself  to  me  as  more  in  harmony  with  the  foi^s  which  I 
observe  in  oar  stshles.  Still  I  do  not  deny  that  it  may  be  posiMhiii 
for  a  certain  qaaat^  of  fat  to  be  elaborated  in  the  bodies  of  hsihi- 
Torous  animals,  under  the  influence  of  a  special  fermeatatioa  of  the 
sugar  which  forms  an  element  in  their  food ;  slthoogh  I  fod  tntipfed, 
from  practical  facts,  that  sugar  plays  no  essentia]  part  in  the  fatten- 
ing of  cattle. 

The  formation  theory,  nevertheless,  is  not  without  data  of  a  very 
curious  and  important  kind,  which  require  notice.     Huber  had  ' 
tluil  bees  fed  upon  honey,  and  even  upon  sugar,  did  not  b^ 


420    FATTY  ELEMENTS  OF  FOOD,  .'..ND  ON  FATTENING. 

power  of  producing  wax  for  a  long  period.  And  Messrs.  Milne 
Edwards  and  Dumas  have  lately  confirmed  the  occasional  accuracy 
at  least  of  this  conclusion.  Their  first  experiments  were  unfavora 
ble  to  the  conclusions  of  the  celebrated  bee-master  of  Geneva.  A 
swarm  fed  with  lump-sugar  yielded  very  insignificant  quantities  of 
wax  ;  three  other  swarms,  placed  in  glazed  hives,  and  fed  on  honey 
and  water,  failed  to  produce  any  wax  ;  but  a  fourth  swarm  gave  a 
totally  different  result. 

The  procedure  by  analysis  was  now  instituted.  The  absolute 
quantity  of  wax  contained  in  the  body  of  a  bee,  or  in  the  bodies  of  a 
certain  number  of  bees,  was  first  ascertained  ;  second,  the  quantity 
of  wax  in  the  combs  constructed  by  the  laborers  was  determined  ; 
third,  the  quantity  of  wax  contained  in  the  honey  consumed  was  dis- 
covered. The  final  result  of  the  inquiry  was,  that  a  swarm  of  2005 
laborers,  after  having  in  the  course  of  a  month  consumed  12889.43 
grs.  of  honey,  had  produced  2407  grs.  of  wax.* 

Granting  the  accuracy  of  this  conclusion,  admitting  that  the  bee 
fed  upon  honey  has  the  power  of  producing  wax,  I  might  still  ask 
whether  it  was  therefore  legitimate  to  conclude  that  the  ox  was 
endowed  with  any  faculty  of  the  same  kind  1  Still,  to  the  interesting 
physiological  fact  above  quoted,  may  be  associated  the  remarkable 
fact  of  the  conversion  of  sugar  into  butyric  acid,  observed  by  Messrs. 
Pelouze  and  Gelis,  a  conversion  effected  by  mixing  a  small  quantity 
of  caseum  with  a  solution  of  sugar,  and  adding  a  sufliciency  of  chalk 
to  neutralize  acid  as  it  was  formed.  This  mixture,  placed  in  a  tem- 
perature of  from  77"  to  86°  F.,  by  and  by  passes  through  a  series  of 
changes,  the  last  term  of  which  is  the  butyric  fermentation. 

This  butyric  acid  is  a  volatile,  colorless,  and  very  limpid  fluid, 
having  an  odor  that  brings  to  mind  at  once  that  of  vinegar  and  rancid 
butter.  Although  it  has  a  resemblance  to  the  acids  which  prevail 
in  different  kinds  of  fat,  it  nevertheless,  by  uniting  with  glycerine, 
constitutes  a  fatty  body,  butyrine,  which  forms  about  one-hundredth 
part  in  the  constitution  of  butter,  and  must  therefore  be  received  as 
one  of  the  elements  of  the  fats ;  and  the  observations  of  Arthur 
Young  would  even  incline  us  to  presume  that  butyric  acid  exerts  a 
favorable  influence  in  the  fattening  of  animals.  Comparative  experi- 
ments satisfied  Young  that  hogs  fattened  more  quickly  on  food  that 
had  become  sour,  than  on  the  same  food  before  it  had  turned.  Now 
it  is  very  probable  that  there  was  production  of  butyric  acid  in  the 
course  of  the  fermentation. 

The  question  in  reference  to  the  formation  of  fat  is  of  much  more 
limited  interest  to  the  farmer  than  to  the  physiologist.  The  agricul- 
turist, in  fact,  cares  little  whether  a  couple  of  pounds  of  honey  con- 
sumed by  a  hive  of  bees  will  give  origin  to  some  10  dwts.  or  so  of 
wax  ;  the  matter  that  concerns  him  is,  as  to  the  degree  in  which 
the  roots  or  tubers  that  he  grows  are  fattening  ;  and  whether  or  not 
he  can  advantageously  substitute  a  cheaper  for  a  more  costly  articlti 
in  his  piggery  or  stalls  1     And  here,  as  in  so  many  other  placei 

•  Vide  Co>iii)tcs  rcnilus  dc  rAcadtinlc  dcs  Sciences  t.  xvii.  p.  131. 


FATTY  ELEMENTS  OF  FOOD,  AND  ON  FATTENING.     421 

practice  got  the  start  of  theory  ;  and  I  own,  with  perfect  humility, 
that  I  think  its  conclusions  are  in  general  greatly  to  be  preferred  ; 
the  universal  custom  of  giving  oil-cake  and  oleaginous  seeds  to  our 
milch-kine  and  fatting  oxen  and  sheep,  appears  to  me  to  supply  an 
argument  of  much  greater  force  than  any  that  can  be  obtained  from 
chemical  researches  pursued  in  the  laboratory. 

Such  articles  as  the  potato  and  the  banana,  which  answer  admi- 
rably for  the  keep  of  hogs  after  they  are  weaned,  are  not  adequate  to 
fatten  them  for  the  butcher  ;  they  contain  but  very  small  quantities 
of  fatty  matter,  and  though  the  animals  will  grow  rapidly  upon  them, 
and  even  attain  to  and  maintain  a  certain  condition,  all  that  is  re- 
quired can  only  be  secured  by  adding  some  other  article  to  the  ration 
that  is  richer  in  oleaginous  or  fatty  principles.  At  Bechelbronn, 
whatever  others  have  said  on  the  subject,  we  find  that  our  hogs  will 
not  fatten  on  potatoes  alone ;  so  that  I  agree  with  Schwertz  when 
he  says,  that  while  hogs  will  get  into  good  flesh  upon  potatoes,  and 
even  seem  to  fatten  for  a  time,  they  soon  cease  from  improving,  and 
only  begin  to  advance  again  when  they  receive  in  addition  an  allow- 
ance of  barley  or  of  split  peas  or  beans. 

A  young  pig  will  consume  about  13  lbs.  of  potatoes  per  diem,  into 
which,  as  analysis  of  the  ashes  informs  us,  there  enters  but  about 
17.2  grs.  of  lime.  But  this  quantity  is  probably  too  small  to  meet 
the  demand  for  bone  earth  in  a  young  animal  in  full  growth,  and 
hence  the  great  advantage  of  the  whey  or  small  quantity  of  skim 
milk  which  is  so  commonly  added  to  the  potato  ration.  It  ought  to 
be  laid  down  as  a  general  rule,  that  young  creatures  as  well  as  adults 
ought  to  have  a  ration  which  contains  the  earthy  elements  of  the 
bony  system,  the  azotized  elements  of  the  flesh,  and  the  fatty  matter 
of  the  fat.  From  a  series  of  experiments  which  I  undertook,  in 
concert  with  Messrs.  Dumas  and  Payen,  it  appears  that  all  the  arti- 
cles acknowledged  the  most  powerful  as  fatteners,  are  those  also 
that  contain  the  largest  proportions  of  fatty  principles.  The  follo>y- 
ing  substances  contain  the  numerical  quantities  of  matter  soluble  in 
et'  er  in  100  parts  : 

Common  maize 8.8       Dryhicem 3.5 

Beaked  Lombardy  maize 7.8        Meadowhay 3.8 

Large  white  Parisian  maize...-     8.1        African  wheat  straw 3.2 

Rice 0.8        Ditto  Alsace 2.2 

Oats 5.5       Ditto  near  Paris 2.4 

Ditto 3.3        Oatstraw 5.1 

Rye 1.8        Beanmeal 2.1 

Rye  flour 3.5        Beans 2.0 

Hard  Venezuela  wheat 2.6        Haricots 3.0 

Hard  African  wheat 2.1        Peas 2.0 

Wheat  flour 2.1        Lentils 2.5 

Ditto 1.4       Potatoes 0.08 

Finebran 4.8       Mangel-wurzel 0.1 

Coarsebran 5.2        Carrots 0.17 

Dryclover 4.0       Oil-cake 9.0 

M.  Payen  found  that  the  oil  was  everywhere  present  in  the  seeds 
of  gramineous  plants.  The  embryo  contains  much,  the  husk  less, 
the  farinaceous  portion  still  less.  But  maize  and  oil-cake  contain 
about  9  per  cent.,  whence  the  universally  admitted  superior  fattening 
power  of  these  two  articles. 

36 


422  FATTY  ELEMENTS  OF  FOOD,  AND  ON  FATTENING. 

If  we  now  discuss  particularly  one  or  more  of  the  rations  or 
allowances  to  oxen  put  up  to  fatten,  or  to  milch-cows,  we  shall  find 
that  they  uniformly  contain  a  larger  quantity  of  fatty  matters  than 
the  secretions,  excretions,  and  fat  which  have  heen  produced  under 
their  influence.  Thus  a  cow,  in  good  condition,  that  produces  72 
pints  of  milk,  containing  3.3  lbs.  of  butter,  while  she  eats  220  lbs. 
of  meadow-hay,  will  have  consumed  more  than  6.6  lbs.  of  matter 
soluble  in  ether — fatty  substances.  The  quantity  of  fat  contained 
in  the  food,  over  and  above  that  which  is  discovered  in  the  milk,  has 
passed  with  the  excrements,  which  are  never  entirely  free  from  sub- 
stances analogous  to  fatty  matters. 

With  a  view  to  comparing  as  accurately  as  is  possible  in  inquiries 
of  this  kind,  the  quantity  of  fatty  matter  contained  in  the  forage 
consumed  by  a  cow,  with  that  found  in  the  milk  and  in  the  excre- 
ments, the  following  experiment  was  made.  A  cow,  Esmeralda, 
No.  6  in  the  stable  at  Bechelbronn,  calved  on  the  26th  of  September, 
and  she  was  put  to  the  bull  again  on  the  4th  of  November.  Up  to 
the  22d  of  January  (inclusive)  Esmeralda  received  the  usual  allow 
ance,  viz  : 

After-math  hay 11  lbs. 

Oil-cake 22  " 

Turnips 66  " 

Wheatchaff. 22  " 

and  the  milk  she   gave  in  the  course  of  the  month  of  January, 
amounted  on  the — 

Pints.  Pints. 

Istto 12.9  12th 12.3 

2d 12.3  13th 11.4 

3d 12.3  14th 11.4 

4th 11.4  15th.: 12.3 

5th 10.5  16th 10.5 

6th 12.3  17th 11.4 

7th 12.3  18th 10.5 

8th 12.9  19th 11.4 

9th 12.3  20th 11,4 

10th 10.5  21st 11.4 

11th 11.4  22d 11.4 

The  average  quantity  of  milk,  therefore,  per  day,  in  the  course 
of  the  week  that  preceded  the  experiment,  was  10.287  pints. 
From  the  23d  of  January,  when  the  ration  was  altered  to — 

Hay 16.5  lbs. 

Chopped  wheat  straw 9.9   " 

Beet-root 59.4   " 

the  quantity  of  milk  yielded  was  : 

January.                                          Pints.  January.                                          Pints. 

23d 11.4  27th 11.6 

24th 10.5  28th 11.4 

25th 10.5  29th IIA 

36th 10.5  30th 11.4 

on  an  average  11.8  pints  per  diem  ;  a  little  more  than  with  the  form- 
er allowance. 

The  excrement  passed  by  this  cow  was  analyzed  during  four  days, 
from  the  24th  to  the  27th  of  January  ;  the  whole  quantity  being 
weighed  moist  every  day,  and  well  mixed,  a  mean  sample  of  about 
0  oz.  in  weight  was  taken  for  analysis.     This  being  stove-dried,  the 


f  ATTY  ELEMENTS  OF  FOOD,  AND  ON  FATTENING.  423 

entire  quantity  of  dry  matter  contained  in  the  moist  excrement  waa 
readily  ascertained : 

Dates.  Moist  excrement.  Dry  excrement.  Milk  in  pints.  Milk  in  Ibi. 

Jan.  24 40.7  lbs.  6.8  lbs.  10.5  13.5 

25 41.8  7.3  10.5  13.5 

26 62.1  9.0  10.5  13.5 

27 43.4  7.1  10.5  13.5 

188.0  30.2  42.0  54.0 

To  ascertain  the  quantity  of  fatty  or  waxy  substances  contained 
in  the  food,  the  several  samples  were  first  treated  with  hot  water, 
then  with  ether,  and  finally  with  a  mixture  of  ether  and  alcohol  boil- 
ing. The  fatty  element  of  the  butter  was  determined  by  Peligot'a 
method. 

Fatty  Matters  in  tbe 
Food  per  c»nt. 

„„„  S  1st  Experiment 3.6 

"*y )2d      ditto 3.9 


Straw 


1st  Experiment 2.4 

2d      ditto 2.0 


Fatty  Matter  in  the 

Excrements  and 

Milk  per  cent. 

Excrements  (dry) S  ^  ^E"'"*:::::::: i.-.lio 

Milli 3.7 

Let  us  say,  that  the  proportion  of  fatty  substance  contained  per 

cent,  in  the  several  articles  consumed  as  food,  was  as  follows — 

Hay 3.7 

Straw 2.2 

Beet 0.1 

Dry  excrements 3.6 

Milk 3.7 

and  we  shall  have  the  results  of  the  experiment  in  this  shape : 

FOOD  CONSUMED  IN  FOUR  DAYS.  EXCREMENTS  AND  MILK  IN  FOUR  DAYS. 

Fatty  matter.  Fatty  matter. 

Beet 237.6  lbs.    1667.3  grs.  Excrements 30.4  lbs.      7688.1  grs. 

Hay 66.0  1776.1  Milk 54.3  14125.7 

Straw 39.6  6113.4  

Fatty  matter  in  excrements 

Fatty  matter  in  food.  .24956.8  and  milk 21813.8 

The  excretions 21813.8 

Fatty  matter  fixed  or 

burned 3143.0 

The  natural  conclusion  from  this  experiment  appears  to  be  this  : 
that  the  cow  extracts  from  her  food  almost  the  whole  of  the  fatty 
matter  it  contains,  and  that  she  converts  this  matter  into  butter. 

It  would  perhaps  be  possible  to  make  the  proportion  of  butter 
contained  in  the  milk  to  vary  within  certain  limits.  It  is  well  known 
that  the  butter  of  cows  in  the  same  district  varies  notably  according 
to  the  nature  and  abundance  of  the  forage ;  the  butter  of  the  same 
country-side,  for  example,  has  been  ascertained  to  contain  66  of 
margarine  to  100  of  oleine  in  summer,  and  186  of  margarine  to  100 
of  oleine  in  winter.  In  the  first  case,  the  cows  are  grazing  on  the 
mountains,  (the  Vosges ;)  in  the  second  they  are  eating  dry  fodder 
in  the  stall.  I  have  besides  had  an  opportunity  to  make  a  direct 
experiment  upon  this  subject,  which  appears  to  me  quite  conclusive 
Having  substituted  for  one  half  the  allowance  of  hay  an  equivalen 


424  FATTY  ELEMENTS  OF  FOOD,  AND  ON  FATTENING. 

quantity  of  rape-cake,  still  very  rich  in  oil,  the  cows  were  kept  in 
excellent  condition  ;  but  the  butter  was  extremely  soft,  and  had  the 
taste  of  rape-seed  oil  to  a  degree  that  was  perfectly  intolerable. 

I  do  not  know  a  single  instance  in  any  of  the  systems  followed  at 
Bechelbronn,  in  which  a  milch-cow  does  not  receive  in  her  ration  a 
quantity  of  matter  analogous  to  fat,  superior  to  that  which  is  con- 
tained in  the  milk  she  yields.  Having  upon  a  certain  occasion  put 
a  cow  exclusively  upon  beet,  I  anticipated  an  unfavorable  effect  on  her 
milk  ;  and  in  fact  a  very  sensible  diminution  in  all  its  valuable  ele- 
ments occurred,  and  the  animal  began  to  suffer.  By  simply  adding 
a  few  pounds  of  straw  which  had  been  taken  away,  the  milk  resumed 
its  standard  quality.  The  two  rations  thus  composed  may  be  con- 
trasted under  the  two  points  of  view  of  contents  in  fat  and  contents 
in  organic  matter. 

In  the  ration  of  beet  and  straw  (beet  119  lbs.,  straw  7|lbs.)  there 
were  140  dwts.  20  grs.  of  fatty  matter  ;  in  that  composed  exclusively 
of  beet  (132  lbs.)  there  were  but  38  dwts.  14  grs.  of  fat.  The  ill  effects 
of  the  beet- root  ration  could  not  be  ascribed  to  deficiency  of  inorganic 
elements,  for  the  phosphate  of  lime  it  contained  amounted  to  37  dwts. 
7  grs. — amply  sufficient  for  all  the  purposes  of  the  economy. 

The  information  we  have  from  M.  Damoiseau,  one  of  the  most 
careful  of  the  observers  who  have  investigated  the  subject  of  the 
production  of  milk,  confirms  us  in  our  views  of  the  necessity  of  fatty 
matters  in  the  daily  ration  of  the  milch-cQw.  The  following  are 
the  elements  of  three  of  the  rations  for  a  cow  in  M.  Damoiseau's 
establishment. 

No.  I.  No. «.  No.  >. 
Beet,  or  mangel-wurzel. .  88  lbs.           Carrots    74  lbs            Potatoes  55  lbs. 

Bran 6.6  "  6.6  "  6.6 

Pollard. 5J  "  5.5  "  5.5 

Lucern 6.6  "  6.6  "  6.6 

Oat-straw 13.2  "  13.2  "  13.2 

Salt 0.11  "  0.11  "  0.11 

121.0  107.0  88.0 

Maximum.  Medium.  Minimum. 

Quantity  of  milk  yielded..  From  25  to  26  pts.        16  to  18  pts.        12^  pts. 

Let  us  now  calculate  the  actual  nutritive  value  of  the  different 
items  in  the  above  rations ;  or,  selecting  one,  let  us  take  that  with 
the  beet  for  particular  consideration,  as  among  the  most  usual. 

6.6  lbs.  of  bran  and  5.5  lbs.  of  pollard  at. .. .  5  per  cent=0.60  of  fatty  matter 

6.6  lbs.  lucern 3        "       =0.33 

13.2  lbs.  oat-straw  5        "       =0.60  " 

1.53 

Whence  it  follows,  that  a  cow  here  received  upwards  of  1|  lbs. 
of  matter  of  a  fatty  nature  with  her  food — a  quantity  more  than  suf- 
ficient to  produce  not  only  16  or  18,  bu.  the  maximum  quantity  of 
25  or  26  pints  of  milk,  very  rich  in  cream.  Did  the  cow  receive  an 
additional  40  lbs.  of  beet-root,  she  would  find  something  like  12  lbs. 
more  of  solid  matter  in  this  article,  composed  especially  of  sugar, 
which  sne  would  burn  to  keep  up  her  temperature,  and  nearly  25 
4wt0.  ol  oily  matter,  which  she  would  transfer  to  her  milk, — to  say 


FATTY  ELEMENTS  OF  FOOD,  AND  ON  FATTENING.  425 

nothing  of  new  azotized  principles  which  would  be  converted  into 
caseine. 

If  we  now,  by  an  easy  transition,  pass  to  the  phenomena  of  fatten- 
ing, we  still  find  that  the  principles  which  have  been  laid  down  can 
be  most  satisfactorily  applied.  Setting  out  from  the  numbers  ob- 
tained from  the  experiments  of  Mr.  Riedesel,  which,  in  many  points, 
agree  with  all  I  have  seen  myself,  we  arrive  at  the  following  con- 
clusions. 

An  ox  weighing  1320  lbs.  avoird.  will  keep  up  his  weight  upon 
about  22  lbs.  of  good  hay  per  diem.  Put  up  to  fatten,  the  same  ani- 
mal would  require  about  twice  this  quantity,  say  44  lbs.,  upon  which 
he  would  gain  at  the  rate  of  about  2  lbs.  per  day. 

Now,  if  we  even  take  Mr.  Riedesel's  conclusions  as  a  little  too  fa- 
vorable, as  giving  at  least  the  maximum  nutritive  value  to  the  hay  and 
its  equivalents,  we  may  still  admit,  with  him,  that  22  lbs.  of  hay  will 
produce  about  17  pints  of  milk,  or  about  2  lbs.  avoird.  of  flesh,  con- 
taining 0.55  lbs.,  or  rather  more  than  |  lb.  of  fat.  Now,  22  lbs.  of 
hay  contain  nearly  12  oz.  12  dwts.  of  principles  soluble  in  ether, 
i.  e.  of  fatty  or  waxy  matter. 

The  fatting  ox,  consequently,  fixes  a  certain  proportion  of  these 
principles  in  the  same  way  as  the  cow.  There  is  only  this  differ- 
ence, that  the  cow  returns  with  the  milk  she  yields  a  considerable 
quantity  of  the  fat  she  finds  in  her  food.  There  consequently  exists 
an  obvious  relation  between  the  formation  of  milk  and  fattening — a 
position  which  would  gain  support,  did  it  require  any,  from  a  note 
which  I  owe  to  the  politeness  of  M.  Yvart,  who,  in  summing  up  a 
long  array  of  facts,  concludes  with  these  words  :  "  The  secretion  of 
milk  appears  to  alternate  with  that  of  fat.  When  a  milch-cow  fat- 
tens, she  loses  her  milk ;"  and  the  converse  of  the  proposition  is  no 
less  true ;  when  we  would  fatten  a  cow,  we  must  let  her  go  dry. 

The  breeds  of  kine  admitted  to  be  the  best  milkers  remain  long 
lean  after  the  calving.  In  some  of  the  short-horned  English  breeds, 
the  quantity  of  milk  is  often  very  considerable  shortly  after  the 
calving ;  but  the  animals  are  much  disposed  to  get  fat,  and  getting 
fat,  the  secretion  of  milk  neither  continues  so  long,  nor  is  it  so  plen- 
tiful, as  in  some  of  the  other  less  improved  kinds.  English  hogs, 
which  become  much  fatter  than  French  hogs,  appear  not  to  be  such 
good  nurses.  Now,  if  we  admit  that  there  is  this  intimate  relation 
between  the  formation  of  milk  and  that  of  fat,  we  are  obviously  very 
near  the  admission,  that  articles  of  food  containing  fatty  substances 
indispensable  to  the  production  of  milk,  are  also  indispensable  to  the 
production  of  animal  fat.  And,  then,  has  it  ever  yet  happened  that 
animals  have  been  fattened  with  food  devoid  of  grease  ?  I  have  not, 
for  my  own  part,  met  with  a  single  fact  which  countenances  such  a 
proposition.  I  have  referred  to  the  distinguished  agriculturist,  who 
attempted  to  fatten  pigs  upon  potatoes,  but  who  only  succeeded  by 
adding  a  certain  quantity  of  graves  to  the  food — an  article  which,  as 
every  one  knows,  conf  ains  a  considerable  proportion  of  fat  in  its  com- 
position. 

M.  Payen  has,  in  fine,  made  some  experiments  which  appear  alto 
36* 


426  FATTY  ELEMENTS  Cf  FOOD,  AND  ON  FATTENING. 

gether  conclusive,  and  from  which  it  follows,  that  two  Hampshire 
hogs  which,  having  consumed  66  lbs.  of  gluten,  and  upwards  of  30| 
lbs.  of  starch,  had  only  gained  17|  lbs. ;  while  other  two  animals  of 
the  same  breed,  having  been  fed  with  99  lbs.  of  the  flesh  of  sheeps' 
heads,  containing  from  12  to  15  per  cent,  of  fat,  had  gained  35  lbs. 
Yet,  judging  from  elementary  analysis,  these  two  rations  were  almost 
identical ;  they  contained  the  same  quantity  of  dry  nutritious  matter. 
The  first  ration  contained  26.4  lbs.  of  dry  gluten,  and  30.4  lbs.  of 
starch  ;  the  second  contained  20.9  lbs.  of  dry  flesh,  and  15.4  lbs.  of 
fat.  The  quantities  of  carbon  and  azote  were,  therefore,  a  little 
higher  in  the  vegetable  than  in  the  animal  ration  ;  but  they  differed 
notably  in  this,  that  the  latter  contained  an  equivalent  of  fat  for  the 
equivalent  of  starch  contained  in  the  former. 

In  a  second  experiment,  four  hogs,  fed  upon  boiled  potatoes,  car- 
rots, and  a  little  rye,  gained  117.7  lbs.  ;  while  other  four  animals, 
of  the  same  age,  and  in  the  same  conditions,  but  fed  upon  sheeps' 
heads,  gained  as  many  as  226.6  lbs. 

In  the  course  of  these  experiments,  M.  Payen  was  struck  with 
this  circumstance,  that  the  increase  in  weight  of  an  animal  that  is  fat- 
tening being  represented  by  50  per  cent,  of  water,  33.3  of  fat,  and 
16.6  of  azotized  matter,  the  conviction  is  forced  upon  us  that  he  ac- 
tually fixes  the  greater  proportion  of  the  fat  of  his  food  in  the  cellu- 
lar tissue  of  his  body.  The  first  hogs,  for  example,  had  eaten  14.74 
lbs.  of  fat,  and  had  gained  11.44  lbs.  in  weight;  the  four  last  re- 
ferred to  had  had  18.48  of  grease,  and  had  increased  14.74  lbs.  in 
weight. 

It  has  now  been  the  practice  for  several  years,  in  various  places, 
to  maintain  hogs  in  considerable  numbers  upon  muscular  flesh,  horse- 
flesh; and  it  has  been  ascertained  that  the  article,  if  extremely 
lean,  though  it  keeps  the  animals  in  good  heart  and  condition,  though 
they  grow  and  thrive  on  it,  yet  they  will  not  fatten.  When  they  are 
to  be  got  ready  for  the  butcher,  they  must,  in  addition,  be  put  upon 
a  course  that  is  known  to  be  proper  to  fatten  them. 

The  scientific  question  of  fattening  having,  of  late  years,  attracted 
very  general  attention,  the  opinions  which  have  now  been  announced 
have  been  very  actively  contested.  Among  other  arguments,  the 
general  freedom  from  fat  of  the  bodies  of  carnivorous  animals,  and 
the  usual  fat  state  of  those  of  the  herbivorous  races,  has  been  cited. 
Whales  have  even  mistakenly  been  included  in  the  list  of  fat  vege- 
table feeders ;  but  it  is  known  to  all  naturalists,  that  the  great  ma- 
jority of  the  whale  tribes,  the  whole  of  those  that  inhabit  the  northern 
seas,  are  carnivorous.  And,  indeed,  the  mention  of  this  fact  leads 
me  to  revert  to  one  of  the  most  curious  problems  in  the  physics  of 
the  globe — that,  to  wit,  presented  by  the  vast  amount  of  animal  life 
amidst  the  waters  of  the  ocean,  and  its  support  by  a  quantity  of 
vegetables  which  to  us  appear  altogether  inadequate  to  such  an  end. 
The  beautiful  researches  of  M.  Morren,  however,  seem  calculated 
to  throw  some  light  on  this  interesting  subject, — that  inquirer  having 
shown  that  certain  animalcules  possess  the  faculty  of  decomposing 
carbonic  acid  in  the  same  way  as  vegetables ;  and  it  is  probably  ia 


FATTY  ELEMENTS  OF  FOOD,  AND  ON  FATTENING.  427 

virtue  of  this  power  that  the  enigma  is  to  be  explained,  of  the  source 
whence  the  myriads  that  people  the  deep  derive.their  food. 

But  is  it  absolutely  true  that  herbivorous  animals  only  abound  in 
fat  1  Who  has  not  seen  fat  dogs  and  cats  ;  and  in  the  Cordilleras, 
where  palm-trees  abound,  there  is  a  particular  species  of  bear,  which 
lives  in  a  great  measure  on  the  oily  palm -nuts  and  young  shoots  of 
the  palm-tree,  which  becomes  remarkably  fat,  and  proves  a  great 
attraction  to  the  tigers  of  the  country.* 

Before  coming  to  a  close  with  this  discussion,  I  think  it  right  to 
refer  to  the  experiments  of  M.  Magendie,  who  has  so  well  establish- 
ed the  fact,  that  the  chyle  of  animals  fed  on  fat  food  contains  a  large 
quantity  of  fat ;  and  that  animals  kept  long  on  such  food  frequently 
become  affected  with  what  is  called  the  fatty  liver. f 

To  sum  up,  then,  experiment  demonstrates  that  hay  contains  a 
larger  quantity  of  fatty  matter  than  the  milk  and  excretions  which  it 
forms  ;  and  that  it  is  the  same  with  all  the  other  mixtures  and  varie- 
ties of  food  that  are  usually  given  to  animals. 

That  oil-cake  increases  the  production  of  butter,  and  that,  like 
maize,  it  owes  the  fattening  properties  it  possesses  to  the  large 
quantity  of  oil  it  contains. 

That  there  is  the  most  perfect  analogy  between  the  production 
of  milk  and  the  fattening  of  animals  ;  that  potatoes,  beet,  carrot,  and 
turnip,  only  fatten  when  they  are  conjoined  with  substances  that 
contain  fatty  matters,  such  as  straw,  corn,  bran,  and  oil-cake  of 
various  kinds. 

That  in  equal  weights,  gluten  mixed  with  starch,  and  flesh  meat 
abounding  in  fat,  have  a  fattening  influence  on  the  hog,  which  differs 
in  the  relation  of  1  to  2. 

Lastly,  that  fat  food — food  which  will  aflford  fat  in  the  digestive 
canal — appears  to  be  the  indispensable  condition  of  fattening.  If  it 
be  necessary  that  the  respiration  be  diminished  or  lessened  in  extent, 
this  is  only  that  the  fatty  substances  taken  into  the  stomach,  and 
which  have  made  their  way  into  the  blood,  may  not  be  oxidated, 
may  not  be  burned ;  not  that  their  formation  may  be  favored. 

All  these  facts  are  in  such  perfect  harmony  with  the  simple  view 
of  assumption  and  assimilation  of  fatty  matters,  that  it  is  difficult  to 
conceive  on  what  foundation  the  opinion  can  repose  which  would 
have  them  composed  out  of  their  elements  in  the  animal  body. 
Nevertheless,  1  am  myself  the  first  to  admit,  that  more  extensive 
experience  may  had  to  the  modification  or  even  entire  change  of 
the  opinion  which  I  advocate.  The  facts  on  which  that  opinion  is 
based,  despite  their  number,  are  not  probably  yet  sufficient  to  }on- 
Btitute  a  perfectly  satisfactory  or  conclusive  theory.    New  researches 

*  These  bears,  evidently,  cease  to  be  carnivorous  while  they  live  on  palm-nuts  and 
leaves.  For  my  own  part,  I  do  not  thinli  the  point  settled  yet.  The  fatty  matter  of 
the  generality  of  vegetables  is  w^ax  rather  than  grease.  And  then  some  of  the  herbiv 
orous  tribes  seem  never  to  get  fat. — Eno.  Ed. 

t  I  may  here  state  the  contrary  fact,  as  announced  to  me  by  a  physiological  friena, 
In  whose  report  I  place  great  reliance,  that  the  chyle  of  animals  fed  with  substances 
that  give  mere  traces  ol  waxy  matter,  contains  fat  or  oil  that  can  be  collected  in  lar£4 
irtfs—Eva  Ed. 


428  ECONOMY  CF  FARM  ANIMALS. 

are,  therefore,  indispensable :  it  would  be  requisite  to  show,  that  a 

cow  kept  on  a  regimen  abundant  in  point  of  quantity,  but  as  poor  as 
possible  in  matters  analogous  to  fat,  will  continue  to  maintain  her 
condition  and  yet  yield  milk  abounding  in  cream  ;  and  that  it  is 
really  possible,  as  some  persons  affirm,  to  fatten  animals  rapidly  on 
roots  and  tubers  alone.* 


CHAPTER  IX. 

OF  THE  ECONOMY  OF  THE  ANIMALS  ATTACHED  TO  A  FARM 
OF  STOCK  IN  GENERAL,  AND  ITS  RELATIONS  WITH  THE 
PRODUCTION  OF  MANURE. 

Agricultural  industry  generally  extends  to  the  breeding  and  fat- 
tening of  cattle  ;  the  breeding,  or  at  all  events  the  maintenance,  of 
horses ;  the  breeding  and  feeding  of  sheep  and  swine.  The  cir- 
cumstances, indeed,  in  which  the  tiller  of  the  ground  sees  himself 
spared  the  necessity  of  attending  to  these  matters,  are  rare  excep- 
tions to  the  general  rule,  and  in  fact  only  occur  where  it  is  easy  to 
obtain  abundant  supplies  of  manure  from  without,  or  in  those  few 
favored  spots  where  the  fertility  of  the  soil  is  such  that  it  continues 
to  yield  its  increase  without  addition  in  the  shape  of  manure.  In 
the  vicinity  of  great  centres  of  population,  where  dung  can  be  bought 
cheap,  or  of  guano  islands,  where  a  cargo  costs  a  trifle,  and  in  some 
tropical  countries,  large  farming  establishments  may  be  found  to- 
tally without  stock  in  the  shape  of  sheep  and  horned  cattle.  But  in 
a  general  way  the  agriculturist  is  obliged  to  give  himself  up  to  the 
care  of  flocks  and  herds  of  one  description  or  another ;  and,  in  fact, 
we  now  know  that  there  is  a  certain  and  very  indispensable  relation 
to  be  maintained  between  the  extent  of  surface  under  crop  and  the 
number  of  cattle  to  be  provided  for,  variable  as  regards  farms  dif- 
ferently situated  and  circumstanced ;  but  invariable  when  circum- 
stances are  the  same,  and  the  system  of  management  pursued  is 
similar  in  its  principal  features. 

The  question  as  to  whether  the  cultivation  of  grain  or  other  use- 
ful plants,  or  the  rearing  of  cattle,  is  more  profitable,  which  is  often 
agitated,  must  receive  a  diflferent  solution  in  regard  to  each  different 
locality.  In  one  place  it  may  be  more  advantageous  to  breed  cattle 
or  horses  ;  in  another  to  rear  or  fatten  them  :  here,  the  production 
of  milk,  butter,  and  cheese,  may  be  the  best  husbandry  ;  there,  the 
growth  of  hay,  (as  for  miles  round  London  on  the  north  and  west ;) 
and  again,  wheat  and  the  other  cereal  grasses  may  be  the  staples  ot 

*  Whoever  would  tr>'  experiments  in  this  direction,  must  be  careful  to  mix  his  food; 
one  article  alone  never  agrees.  The  Americans  say,  a  pig  will  die  upon  ptmipkins  and 
upon  apples  alone  •  but  he  will  live  and  fatten  on  a  mixture  of  the  two.  I  have  my- 
self seen  scores  of  oxen  fattened  upon  turnips,  with  a  moderate  allowance  of  straw  or 
bog-hay ;  and  have  seen  pigs  get  into  admirable  condition  for  the  butcher  op  itUe  mort 
th%n  potatoes.— Eno.  £o. 


ECONOMY  OF  FARM  ANIMALS.  429 

prod  iction.  Even  supposing  that  the  growth  of  grain  is  that  which 
is  most  advantageous  on  the  whole,  it  by  no  means  follows  that  the 
farmer  shall  give  himself  up  to  this  exclusively ;  it  is  seldom  that 
he  can  do  so,  indeed ;  he  must  have  manure,  and  this  entails  the 
necessity  of  keeping  cattle.  If  the  latter,  however,  be  the  least 
profitable  item  in  the  economy  of  a  particular  domain,  it  will  of 
course  be  kept  within  as  narrow  limits  as  possible. 

In  many  places  where  the  land  is  well  adapted  to  the  plough,  and 
where  the  production  of  grain  is  unquestionably  profitable,  stock  ap- 
pears to  offer  few  advantages  ;  it  sometimes  happens,  indeed,  that  the 
balance  as  regards  the  stall  and  cow-house  is  on  the  wrong  side  for 
the  farmer,  when  the  actual  value  of  the  forage  that  has  been  con- 
sumed is  taken  into  the  account.  The  loss  is  only  made  up  for  by  the 
manure,  which  is  in  fact  the  return.  This  is  the  view  that  M.  Crud 
obviously  takes  when  he  speaks  of  the  stock  upon  a  farm  as  a  neces- 
sary evil.*  I  am  far  from  participating  in  his  opinion  ;  the  cattle 
upon  a  farm  are  no  evil,  though  they  may  be  very  necessary.  To 
be  satisfied  of  this,  it  is  enough,  in  fact,  to  recollect  the  principle 
which  has  been  established  in  treating  of  rotation  courses,  viz : 
That  in  no  case  is  it  possible  to  export  a  larger  quantity  of  organic 
matter,  and  particularly  of  organic  azotized  matter,  from  a  farm, 
than  is  represented  by  the  excess  of  the  same  description  of  matter 
contained  in  the  manure  consumed  in  the  course  of  the  rotation. 
By  acting  otherwise,  the  standard  fertility  of  the  soil  would  inevt 
tably  be  diminished. 

This  principle  recognised,  and  I  believe  that  it  cannot  be  disputed, 
it  is  obvious  that  a  portion  of  the  produce  of  the  fields  must  be  re- 
turned to  them  to  fecundate  them  anew,  and  it  is  precisely  this  por- 
tion of  the  forage  crops  destined  to  furnish  manure  that  must  be 
consumed  in  the  stable  and  cow-house.  Reasoning  abstractly,  the 
forage  plants  which  it  is  not  intended  should  quit  the  farm,  might  be 
buried  directly  as  manure,  without  being  made  to  pass  through  the 
bodies  of  animals ;  their  fertilizing  influence  on  the  soil  would  come 
out  sensibly  the  same ;  and  this  is  what  is  done,  in  fact,  so  often  as 
we  manure  by  smothering.  But  we  have  scarcely  made  the  first 
step  in  the  rudiments  of  agriculture  before  we  discover  the  immense 
advantages  of  following  the  usual  custom,  which  first  employs  as 
forage  for  cattle  the  crops  that  are  grown  with  a  view  to  the  pro- 
duction of  manure.  And  we  shall  by  and  by  find,  in  fact,  that  by 
adding  to  that  portion  of  these  crops  a  supplement  of  forage  plai  ts 
which  it  would  be  legitimate  to  export,  without  trenching  upon  the 
fundamental  principle  above  laid  down,  we  obtain  the  same  quantity 
of  manure,  and  turn  the  whole  of  this  supplement  into  useful  forces, 
or  into  animal  products  which  possess  a  market  value  greatly  supe- 
rior to  that  of  the  forage  before  its  assimilation.  It  is  only  the  price 
of  this  portion  of  the  forage,  fixed  or  modified  by  the  cattle  on  the 
farm,  which  can  fairly  be  set  down  to  the  debit  account  of  wool 
grown,  of  power  created,  and  of  flesh  and  dairy  articles  produced. 

*  Thewet.  and  Pract.  Economy  of  Agricul.  vol.  ii.  p.  235,  (in  French.) 


430  HORNED  CATTLE. 

As  to  the  forage  plants  which  are  immediately  turned  into  manuie, 
it  seems  to  me  impossible  to  regard  them  as  possessed  of  the  proper 
market  value ;  the  farmer  could  not  have  sold  them  at  this.  In  my 
mode  of  looking  at  the  thing,  the  cost  of  producing  the  forage  crop, 
and  the  value  that  it  actually  has,  constitute  a  circulating  capital, 
the  annual  interest  of  which,  estimated  at  a  certain  rate,  expresses 
the  true  cost-price  or  value  of  the  manure  employed  in  the  3ourse 
of  a  rotation.  In  a  word,  in  my  eyes,  the  value  of  the  manure 
which  gives  fertility  to  the  soil  is  represented  by  the  price  of  the 
labor,  the  rent  charge,  &c. — by  the  general  outlay  entailed  by  the 
growth  of  the  forage  from  which  it  is  obtained. 

I  shall  endeavor,  by  and  by,  to  illustrate  this  topic  by  examples  ; 
but  in  order  thoroughly  to  understand  this  mode  of  estimating  the 
price  of  manure,  there  are  several  elements  wanting,  which  I  pro- 
pose to  assemble  in  this  chapter-  With  this  view,  I  shall  first  pre- 
sent the  facts  which  I  have  been  able  to  collect,  or  which  I  have 
myself  had  an  opportunity  of  observing  in  reference  to  the  economy 
of  the  domestic  animals  attached  to  a  farm  ;  and  I  shall  then  make 
an  attempt  R)  deduce  the  relation  that  exists  between  the  consump- 
tion of  forage  and  litter,  animal  reproduction  and  increase,  and  the 
formation  of  manure. 

^  HORNED  CATTLE. 

It  were  foreign  to  the  purpose  of  this  work,  did  I  enter  into  the 
natural  history  of  the  animals  that  are  usually  attached  to  farming 
establishments  ;  neither  will  I  pretend  to  discuss  the  relative  merits 
of  the  different  breeds  of  sheep  and  oxen,  nor  speak  of  the  best 
methods  of  improving  them.  I  confine  myself  to  the  varieties  which 
I  have  on  my  own  farm,  or  which  I  see  on  the  farms  of  my  neigh 
bors,  and  upon  which  I  have  opportunity  of  making  daily  observa- 
tions. It  will  be  enough  if  I  give  a  brief  summary,  in  this  place, 
of  the  general  principles  admitted  by  practical  men  of  the  highest 
name  and  authority  upon  these  points.* 

Between  the  external  forms  of  animals  and  the  internal  organs 
essential  to  life,  there  is  the  most  obvious  and  intimate  connection. 
A  broad  and  deep  chest  is  the  sure  indication  of  ample  lungs  and  a 
good  general  constitution.  The  pelvis,  or  bony  cincture  formed  by 
the  rump  and  haunches,  ought  to  be  spacious  in  the  females.  A 
small  head  is  generally  the  indication  of  a  good  kind.  Horns  in  our 
domestic  animals  must  be  regarded  as  objectionable  rather  than  use- 
ful ;  and  by  adopting  measures  which  tend  to  repress  their  growth, 
we  undoubtedly  favor  both  the  prodiiction  of  flesh  and  wool.  The 
strength  of  animals  depends  far  more  on  the  degree  in  which  their 
muscular  system  is  developed  than  on  the  mass  of  their  bones ;  it  is, 
besides,  flesh,  not  bone,  that  has  value  in  the  butcher's  eyes  ;  so 
that  the  farmer's  business  is  by  all  means  to  strive  after  a  delicate 
but  well-covered  skeleton.     Animals  which  have  been  indifferently 

*  Cllne,  in  General  Report  of  Scotland  ;  Communication  to  the  Board  of  Agrlcul 
tore ;  Bpencer  on  the  choice  of  male  animals  for  breeding  from:  Cully's  Introduciioti, 
|(C.,  on  live  nUK^  kc.  .  -^ 


BREEDING.  431 

fed  while  young,  have  often  the  bony  system  very  disproportionately 
developed. 

Two  modes  are  generally  followed  with  a  view  to  improving  the 
external  shape  of  domestic  animals.  One  of  these  consists  in  only 
breeding  from  animals  of  the  most  faultless  forms  of  the  same  race, 
and  generally  of  close  degrees  of  kindred  ;  another  in  crossing 
females  with  the  males  of  a  neighboring  race,  each  possessing  in 
the  greatest  degree  the  qualities  which  it  is  held  desirable  to  trans- 
mit to  the  future  race.  The  former  of  these  plans  is  spoken  of  as 
the  method  of  breeding  in  and  in ;  the  second  as  the  method  hy 
crossing. 

Certain  disadvantages  have  been  stated  as  belonging  to  the  sys- 
tem of  breeding  in,  by  the  side  of  several  unquestionable  and  more 
immediate  advantages.  While  the  race  acquires  small  bones  and 
shows  a  decided  disposition  to  take  on  fat  readily,  it  is  said  after 
several  generations  to  lose  in  constitution,  to  become  more  subject 
to  disease  ;  the  cows  to  give  less  milk,  and  the  males,  in  losing  their 
characteristic  masculine  forms,  to  show  themselves  less  fit  for  pro- 
pagation. The  English  breeders  who  take  this  view  of  the  subject, 
are,  therefore,  in  the  habit  of  having  recourse  to  males  of  the  same 
race,  but  bred  at  a  distance  from  themselves.  I  must  for  my  own 
part  say,  that  T  have  seen  no  reason  to  admit  any  ill  effects  from 
propagation  continued  in  the  same  direct  line.  Our  live-stock  at 
Bechelbronn  has  not  been  otherwise  renewed  for  a  very  long  time, 
and  without  the  race  appearing  to  suffer  in  any  way ;  our  bulk,  on 
the  contrary,  have  very  much  improved. 

Mr.  Cline  insists  greatly  on  the  selection  of  females  not  only  of 
good  shape,  but  so  much  above  the  mean  height  as  to  approach  the 
standard  of  the  males.  When  the  bull  is  very  much  larger  than  the 
cow,  the  progeny  is  apt  to  fall  off  instead  of  improving  ;  the  reason 
for  which  Mr.  Cline  finds  in  the  large  size  of  the  foetus,  the  issue 
of  a  large  male,  which  a  small  female  can  neither  accommodate 
properly  in  her  womb,  send  easily  into  the  world,  nor  suckle  duly 
when  it  is  born.  Whatever  we  think  of  this  explanation,  there  can 
be  no  doubt  of  the  propriety  of  giving  the  principle  pointed  at  the 
most  careful  consideration  in  practice.  Mr.  Cline  refers  to  the  great 
improvement  that  has  been  effected  in  the  breed  of  English  horses 
mainly  through  crosses  with  small  barbs  and  Arabian  stallions  ;  the 
introduction  of  Flemish  mares  would  upon  the  same  principle  have 
been  another  means  of  still  further  improving  the  race.  The  neg- 
lect of  this  principle,  Mr  Cline  is  of  opinion,  lies  at  the  bottom  of 
the  numerous  failures  and  disappointments  that  have  been  encoun- 
tered in  attempts  to  improve  the  breed  of  horses.  A  striking  illus- 
tration of  it  occurred  some  years  back,  when  bay  horses  of  great 
height  were  in  particular  request ;  the  Yorkshire  breeders  had 
their  mares  covered  by  the  tallest  stallions  that  could  be  found  ;  but 
they  immediately  found  that  the  progeny  was  merely  long-legged, 
that  it  was  narrow-chested,  and  without  either  weight  or  bottom. 

Spencer  acknowledges  with  breeders  in  general  that  the  bodily 
»nd  constitutional  qualities  are  almost  always  those  that  preponder- 


432  MANAGEMENT  OF  CATTLE. 

ated  in  ancestors,  and  that  the  qualities  of  the  father  predominate 
in  the  posterity,  particularly  as  regards  oxen  and  sheep.  This  point 
settled,  the  choice  of  a  good  male  is  evidently  the  first  point  of  con- 
sequence in  attempting  to  improve  a  breed.  As  it  is  not  possible, 
however,  to  find  either  a  bull,  or  a  tup,  or  a  stallion,  quite  perfect, 
the  one  must  be  chosen  that  is  most  free  from  defect,  particularly 
the  defect  or  defects  which  we  have  it  in  view  to  correct  in  our 
breeding  animals,  our  cows,  ewes,  and  mares.  Certainly  no  reason- 
able breeder  would  bring  together  animals  that  presented  similar  de- 
ficiencies ;  on  the  contrary,  he  will  strive  to  have  his  female  served 
by  the  male  which  shows  all  the  qualities  in  the  very  highest  degree 
that  are  most  wanting  in  her.  On  the  whole,  the  association  of 
animals  of  the  same  race  appears  to  me  the  best  mode  of  continuing 
desirable  qualities,  especially  when  this  is  conjoined  with  ample  sup- 
plies of  good  food  to  the  young.  The  influence  of  feeding  is  im- 
mense ;  in  my  own  neighborhood  I  see  that  the  progeny  of  the 
Bechelbronn  bulls  are  often  inferior  both  in  stature  and  shape  to 
those  that  are  brought  up  in  our  own  stables. 

Great  size,  however,  is  not  always  to  be  regarded  as  an  improve- 
ment ;  height  is  by  no  means  a  constant  indication  of  vigor  of  con- 
stitution. Improvement  in  those  particulars  of  form  and  stature 
which  are  ascertained  to  be  best  suited  to  the  circumstances  of  the 
locality,  the  climate,  the  pasture,  &c.,  are  the  points  to  be  especially 
attended  to.  It  is  above  all  indispensable  to  breed  animals  of  vigor- 
ous constitution  :  over-refinement  of  original  races  has  often  led  to 
indiflferent  conformation  of  body,  and  to  undoubted  delicacy  of  con- 
stitution, which  has  rendered  the  herd  or  the  flock  much  more  ob- 
noxious to  attacks  of  epizootic  diseases. 

The  degree  of  refinement  of  an  original  stock  is  evidently  con- 
nected with  the  quantity  and  quality  of  the  forage  of  the  district. 
In  cold  and  mountainous  districts,  where  the  herbage  is  scanty,  it  is 
necessary  to  restrain  the  ambition  of  having  highly-improved  stock 
within  considerably  narrow  limits  ;  in  such  circumstances,  the  grand 
aflfair  is  to  have  a  hardy  race,  not  over  nice  in  its  food,  which,  through 
a  considerable  portion  of  the  year,  consists  of  but  coarse  grass. 

The  ox  {bos  taurus)  has  been  reduced  to  domesticity  from  the 
remotest  ages,  and  nothing  but  conjecture  can  be  offered  with  regard 
to  its  original  race.  The  animal  accommodates  himself  with  won- 
derful facility  to  the  most  opposite  climatic  circumstances ;  he  mul- 
tiplies with  astonishing  rapidity  in  the  hottest  regions  of  the  tropics ; 
unknown  at  the  period  of  the  conquest,  he  has  now  overrun  the 
steppes  of  the  vast  basins  of  the  Oronoco  and  the  Amazons ;  and 
is  met  with  in  vast  herds  on  the  highest  and  coldest  table-lands  of 
the  Andes,  even  up  to  the  line  of  perpetual  snow  ;  wherever  there 
is  food,  he  appears  to  thrive  ;  the  extremes  of  temperature  seem  to 
have  little  or  no  influence  upon  him. 

The  buffalo  (the  bos  bubulus  of  naturalists)  is  the  only  other  mem- 
ber of  this  family  that  has  been  domesticated.  He  is  fond  of  warmth, 
and  is  supposed  to  have  been  introduced  into  Italy  towards  the  sixth 
century,  from  Eastern  Asia.     The  buffalo  is  also  found  in  Hungary 


MANAGEMENT    OP   CATTLE.  433 

and  Greece ;  and  wherever  he  is  met  with,  he  is  made  serviceable  as 
a  beast  of  draught  and  burden,  and  as  food. 

In  breeding  oxen,  the  great  consideration  is  the  bull.  According 
to  Thaer,  the  bull  ought  to  have  a  short  thick  neck,  the  head  short 
and  small,  the  forehead  broad  and  curled,  the  eyes  black  and  spark- 
ling, the  ears  long  and  well  placed,  the  chest  broad  and  deep,  the 
body  long,  the  legs  short  and  columnar  in  shape.*  A  well-made 
bull  would  serve  seventy  or  eighty  cows  were  the  season  spread 
equally  over  the  whole  year  ;  but  as  it  is  not  so,  Thaer  thinks  that 
twenty  is  as  many  as  can  properly  be  given  to  the  same  animal ;  and 
this,  in  fact,  is  the  number  which  we  adopt  at  Bechelbronn. 

The  cow  gives  more  milk  than  any  animal  known.  A  great  va- 
riety of  external  signs  of  a  good  milker  have  been  particularized  ; 
but  it  may  be  said  that  there  is  none  infallible.  In  a  general  way,  I 
think  that  race  has  much  to  do  with  the  point ;  the  cow  that  is  the 
offspring  of  a  mother  of  a  good  kind,  and  a  free  milker,  will  herself 
be  a  good  milker  also.  I  will  only  a<dd,  that  among  the  milch-kine 
which  I  have  had  an  opportunity  of  observing,  those  that  showed 
little  tendency  to  take  on  fat,  while  they  kept  their  appetite,  have  ap- 
peared to  me  to  yield  milk  in  largest  quantity,  and  for  the  longest  time. 

The  age  at  which  it  is  advisable  to  put  heifers  to  the  bull,  depends 
a  good  deal  on  the  way  in  which  they  have  been  kept  and  brought 
up,  and  also  on  their  growth.  Young  animals  of  a  good  kind,  that 
have  been  well  fed  from  the  birth,  and  received  all  the  care  which 
contributes  so  powerfully  to  their  development,  will  be  ready  to  re- 
ceive the  bull  when  they  are  between  a  year  and  a  half  and  two 
vears  old.  At  Bechelbronn,  we  bull  the  greater  number  of  our 
heifers  at  the  age  of  about  eighteen  months.  Whenever  they  enter 
into  heat  with  any  thing  like  force,  whatever  their  age,  they  ought 
to  be  put  to  the  bull,  or  there  is  risk  of  the  disposition  to  receive  him 
dying  away,  and  never  returning ;  the  heifer  then  begins  to  lay  on 
fat,  and  ever  after  refuses  the  male.  The  rule,  however,  is  not  to 
allow  the  young  female  to  be  leaped  until  she  is  nearly  at  her  full 
growth  ;  this,  in  fact,  is  the  season  when  the  desire  for  the  male 
usually  first  shows  itself. 

If  there  be  no  new  indication  of  heat,  in  the  course  of  three  or 
four  weeks  after  the  male  has  been  admitted,  there  is  reason  to  be- 
lieve that  the  animal  is  pregnant.  The  cow  goes  with  calf  about 
forty  weeks  ;  the  delivery  generally  takes  place  between  the  277th 
and  the  299th  day  after  the  access  of  the  bull ;  but  periods  so  short 
as  240  days,  and  others  so  long  as  321  days  have  been  observed.f 

The  calf  that  is  brought  up  with  proper  care  is  generally  allowed 
to  suck  for  five  or  six  weeks  ;  but  it  sometimes  happens  that  even 
at  three  weeks  old  the  quanity  of  milk  supplied  by  the  mother  is 
insufficient  :  an  additional  quantity  of  food  is  therefore  requisite. 
One  of  the  best  drinks  for  calves  is  made  by  mixing  a  proper  quantity 
of  oil-cake  with  tepid  water ;  the  large  proportion  of  vegetable  ca- 
Beum,of  oily  matter,  and  of  phosphates  which  the  substance  contains, 

•  Principles  of  Agriculture,  vol.  iv.  p.  296. 

t  Teissier  in  Annals  of  French  Agriculture,  vol.  Ix.  2d  series. 

37 


134  REARING   CALVES. 

makes  it  peculiarly  appropriate  food  for  calves  ;  difiused  in  water,  it 
ill  fact  bears  a  close  resemblance  to  milk  in  point  of  chemical  com- 
position. It  is  now,  too,  that  the  calf  begins  to  play  with  a  little 
hay,  so  that  it  is  always  advisable  to  place  some  within  his  reach, 
the  finest  and  softest  portions  being  picked  out. 

But  it  is  by  no  means  necessary  that  the  calf  should  ever  be  allow- 
ed to  suck ;  it  drinks  without  difficulty,  or  can  be  made  to  drink,  as 
every  dairy  man  and  woman  knows,  by  putting  a  finger  or  two  into 
the  animal's  mouth  under  the  surface  of  the  drink.  A  little  warm 
water  is  added  to  the  milk  during  the  first  few  days,  in  order  to  give 
it  due  warmth.  Some  begin  from  the  very  first  to  measure  the 
milk ;  but  those  who  are  best  informed  upon  the  subject  of  breeding 
and  rearing  do  nothing  of  the  kind.  Crud  allows  his  calves  to  drink 
as  much  milk  as  they  will  take  for  the  first  week  After  this  time 
they  have  an  allowance  of  about  seven  pints  of  new  milk  mixed  with 
the  same  quantity  of  fresh  whey.  They  are  weaned  at  seven  weeks. 
From  the  age  of  between  nine  and  ten  weeks  to  a  year,  a  calf  will 
consume  about  a  fourth  of  the  ration  of  a  grown  cow,  say  6^  lbs.  of 
hay  per  diem.  During  the  second  year,  the  allowance  of  hay  may 
be  estimated  at  about  13  lbs.,  or  a  little  more ;  and  in  the  third  year 
it  will  amount  to  between  19  and  20  lbs.  This  is  to  be  understood 
of  cattle  brought  up  carefully  but  frugally. 

In  some  of  the  best  dairies  of  Switzerland,  the  procedure  is  different. 
During  the  first  six  weeks  the  calves  are  allowed  to  drink  as  much 
milk  as  they  will  take  without  a  surfeit.  At  a  month  old,  they  are 
served  with  chopped  hay  and  roots,  or  better  still,  if  the  season  ad- 
mits of  it,  with  green  clover  or  lucern,  which  they  have  at  discretion 
till  they  are  seventy  days  old.  Treated  in  this  way,  a  calf  is  nearly 
twice  as  large  and  twice  as  heavy  as  one  that  has  been  brought  up 
economically.  During  the  remaining  295  days  that  make  up  the 
first  year,  the  animal  is  allowed  from  8  to  9  lbs.  of  hay ;  and  this 
quantity  is  doubled  during  the  second  year.  By  proceeding  in  this 
way,  a  heifer  at  two  years  old  may  herself  be  a  mother  and  contri- 
buting to  the  produce  of  the  dairy. 

Our  procedure  at  Bechelbronn  is  calculated  on  the  Swiss  plan. 
The  cfUves  suck  till  they  are  six  or  seven  weeks  old,  being  put  to 
the  cows  night  and  morning.  Any  thing  they  leave  is  milked  off. 
After  numerous  trials  by  gauging  and  weighing,  I  find  that  our 
calves  take  each  during  the  forty-two  days  they  are  allowed  to  suck, 
from  528  to  600  pints  of  milk  ;  in  other  words,  from  14^  to  18|  pints 
per  diem.  The  quantit;^  of  milk  which  a  calf  takes  immediately 
after  its  birth,  does  not  indeed  amount  to  any  thing  like  even  the 
smaller  of  these  quantities ;  still  it  is  considerable. 

A  calf  which  weighed  at  its  birth  on  the  18th  of  May  108.9  lbs., 
after  having  sucked,  weighed  112.4  lbs. ;  so  that  it  had  taken  3.5  lbs. 
of  milk  to  its  meal ;  and  as  it  had  two  of  these  in  the  day,  7.0  lbs. 
in  all.  The  same  calf,  thirteen  days  afterwards,  weighed  130.9  lbs  ; 
and  after  having  sucked,  139.0  lbs. ;  it  had  therefore  taken  8.1  lbs. 
to  its  meal,  or  16.2  lbs.  per  day. 

About  the  third  week  after  birth,  our  calves  have  hay  of  the  best 


REARING    CALVES.  435 

quality  set  before  them ;  they  take  very  little  at  first,  but  they  soon 
get  accustomed  to  it,  and  at  weaning  time  it  commonly  suffices  for 
their  support.  It  may  happen,  however,  that  at  this  period  they  fall 
off  a  little,  but  they  soon  recover  again ;  still,  if  any  of  them  appear 
delicate,  it  will  be  prudent  to  allow  about  a  couple  of  quarts  of  milk 
a  day  mixed  with  water,  for  some  little  time,  which  is  gradually 
withdrawn  as  the  animal  becomes  accustomed  to  its  new  food. 

Calves  grow  with  great  rapidity  during  the  suckling  time.  The 
only  experimental  data  with  which  I  am  acquainted  in  regard  to  the 
increase  of  weight  of  calves  during  the  first  period  of  their  lives,  are 
those  of  M.  Perrault  de  Jotemps.  These  observations  I  shall  asso- 
ciate with  those  which  I  have  myself  made  at  Bechelbronn,  where, 
by  a  happy  coincidence,  we  have  the  same  Swiss  race  of  cattle  as 
Messrs.  Perrault  at  Feuillasse.  The  weight  of  three  calves  at  birth 
was  found  by  M.  Perrault  to  be : 

No.l 70.4  lbs. 

No.2 88.8 

No.  8 80.8 

Average 78.0 

At  Bechelbronn  the  weight  of  six  calves  at  birth  was : 

No.  1,  bom  in  May 108.9  lbs 

February 88.0 

Ditto 90.2 

April 100.1 

June 88.8 

May 101.2 

Average 96.2 

M.  Ernest  Perrault  found  that  a  calf,  No.  1,  during  the  first 
eighteen  days  of  its  life  increased  on  an  average  2.8  lbs.  per  diem  ; 
No.  2  increased  at  the  rate  of  1.8  lbs.  per  day ;  and  No.  3  at  the 
rate  of  2.7  lbs.  per  day ;  average  increase  2.4  lbs.  per  day.  An- 
other calf,  born  at  Feuillasse,  which  weighed  101.2  lbs.,  wien  nine- 
teen days  old  weighed  151.2  lbs. ;  so  that  it  had  gained  50  lbs.,  or  at 
the  rate  of  2.6  lbs.  per  diem ;  a  rate  which  corresponded  precisely 
with  what  was  observed  in  the  case  of  nine  other  calves  fed  for  the 
butcher,  the  average  increase  of  which  per  diem  was  2.7  lbs.,  during 
which  each  has  had  about  19.3  pints  of  milk  daily. 

The  conclusions  come  to  at  Bechelbronn  bear  a  close  resemblance 
to  those  of  Feuillasse : 

A  calf  which  at  birth  weighed ....  108.9  lbs. 
Weighed  13  daya  afterwards 139.0 

Increase  in  12  days 80.1     Increase  per  day,  2JJ  lbs. 

A  calf  born  12th  of  Feb.  weighed. .  88.0  lbs 
On  the  80th  of  March  it  weighed.  .171.6 

Increase  in  46  days 88.6     Increase  per  day,  1.8. 

The  same  calf,  weaned  the  2l8t  of 
April,  weighed 198.6  lbs. 

Increase  in  21  days 22.0      Increase  per  day,  1.08. 

It  is  obvious,  therefore,  that  from  the  time  of  weaning,  the  growth 
ceases  to  be  so  rapid  ;  the  transition  from  the  milk  diet  to  one  of 


436  REARING     CALVES. 

Iiard  dry  food,  is  often  critical  for  young  animals ;  and  I  have  al- 
ready said  that  it  is  one  at  which  they  frequently  lose  weight. 

If  we  reckon  the  daily  increase  from  birth,  that  is  to  say,  for  69 
days  of  mixed  alimentation,  we  have  1.5  lb.  for  the  quantity. 

Crescent,  bom  the  27th  of  June,  weighed. ..  88.8  lbs. 
Eleven  days  later 112.1 

Increase 23.3     per  day,  2.1  lbs. 

At  the  ago  of  87  days  he  weighed 188.1 

Increase  in  26  days 27.1      per  day,  2.5 

Six  days  afterwards  he  weighed 202.4 

Increase  in  6  days 14.8     per  day,  2.8 

Another  calf  at  birth  weighed 101.2 

At  weaning,  aged  41  days 189.2 

Increase 88.0      perday,2.1 

These  various  observations  give  about  2.2  lbs.  for  the  average 
daily  increase  of  a  calf  in  weight  during  the  period  it  is  sucking. 
The  data  of  M.  Perrault  make  a  little  higher,  2.7  lbs.  So  that  it 
may  be  assumed  that  a  calf  which  is  receiving  from  15  to  19  pints 
of  milk  in  the  day,  will  be  gaining  2.48,  or  very  nearly  2J  lbs.  in 
weight  per  diem. 

It  will  readily  be  understood  that  in  places  where  milk  is  of  con- 
siderable value,  as  in  the  neighborhood  of  cities,  the  farmer  may  find 
his  profit  in  selling  that  article  directly  rather  than  in  turning  it  into 
veal  or  beef,  more  especially  if  the  usage  of  the  district  be  to  give 
the  calves  milk  till  they  are  three  or  even  four  months  old.  Noth- 
ing, in  my  eyes,  can  justify  such  a  needless  expenditure  of  milk ; 
especially  since  I  have  had  an  opportunity  of  witnessing  what  I  may 
call  the  natural  course  of  rearing  cattle  in  the  steppes  of  South 
America.  There  the  young  animals  only  receive  milk  in  any  thing 
like  quantity  for  two  or  three  weeks ;  they  soon  get  accustomed  to 
live  on  grass.  In  the  warmer  countries  of  the  earth,  too,  cows  give 
much  less  milk  then  they  do  in  temperate  latitudes,  and  the  secre- 
tion also  dries  up  much  sooner.  The  value  of  the  milk,  and  the 
high  price  of  butter  and  cheese,  are  unquestionably  at  the  bottom 
of  the  immense  slaughter  that  takes  place  in  France  among  the 
calves  even  at  a  very  early  age,  when  they  are  fat,  but  do  not  weigh 
more  than  from  110  to  112  lbs.  This  circumstance  undoubtedly 
Btands  in  the  way  of  the  production  of  meat  in  that  country,  and 
causes  the  notorious  scarcity  of  meat  of  the  best  quality.  Of  the 
two  millions  of  calves  which  it  is  calculated  are  slaughtered  in 
France,  I'oths  are  killed  before  they  are  a  month  old,  and  when  they 
do  not  weigh,  one  with  another,  more  than  from  90  to  110  lbs.  But 
we  have  seen  that  at  two  montlis  old  the  weight  will  have  increased 
to  from  154  to  176  lbs.,  more  than  half  as  much  again  ;  so  that,  by 
merely  keeping  the  animals  for  one  month  more,  the  quantity  of 
butcher-meat  brought  to  market  would  be  increased  by  about 
120,000,000  lbs.* 

It  does  not  by  any  means  follow,  however,  as  the  excellent  au. 
thority  I  have  quoted  seems  to  think,  that  this  increase  of  butcher, 
meat  would  add  to  the  actual  amount  of  food  produced  by  the  agrL 
•  Perrault  de  Jotemps,  in  Journal  d'Agrlcnlture,  t.  v. 


REARING    CALVES. 


43t 


cultural  industry  of  the  country.  To  produce  2  lbs.  of  veal,  in  fact, 
I  have  shown  that  something  like  22  lbs.  of  milk  must  be  consumed  ; 
but  it  is  evident  that  1,200,000,000  of  pounds  of  milk  represent  an 
amount  of  nutritive  matter  superior  in  value  to  120,000,000  of  pounds 
of  veal.  Could  the  production  of  the  additional  quantity  of  meat  in 
the  course  of  the  second  month  be  eflfected  by  means  of  any  other 
food  less  costly  than  milk,  which  is  itself  a  fluid  of  great  value  as 
food,  with  ordinary  forage,  for  example,  or  linseed  tea,  or  oil-cake, 
&c.,  the  state  of  the  question  would  be  changed,  and  there  would 
then  be  no  doubt  of  the  advantage  to  the  community  of  the  addi- 
tional supply  of  butcher-meat.  This  indeed  is  so  well  understood, 
that  all  the  efforts  which  have  been  made  to  improve  upon  the  ordi- 
nary and  simply  natural  mode  of  rearing  young  cattle  have  been 
directed  with  a  view  to  economizing  milk.  The  interesting  work 
of  M.  Ernest  Perrault,  from  which  I  am  about  to  make  several  ex- 
tracts, was  not  written  with  any  other  purpose. 

M.  Perrault  set  out  with  the  view  of  ascertaining  experimentally, 
1st,  whether  the  large  quantity  of  milk  generally  allowed  to  sucking 
calves  is  really  indispensable,  and  whether  it  is  possible  to  diminish 
it  without  detriment  to  the  animals ;  2d,  whether  a  portion  of  the 
milk  can  be  replaced  by  hay-tea,  an  article  prepared  by  pouring  14 
or  15  pints  of  boiling  water  upon  a  pound  of  fine  meadow-hay,  and 
infusing  for  a  few  hours. 

The  observations  were  made  upon  three  calves  taken  after  wean- 
ing. A  was  kept  for  94  days  on  the  usual  allowance  to  calves  at 
Feuillasse ;  B  had  a  smaller  quantity  of  milk,  and  from  42d  day 
after  birth  had  an  increasing  allowance  of  solid  food ;  C  in  the 
course  of  the  comparative  experiment  had  476  pints  of  hay-tea,  and 
as  it  is  impossible  to  regard  the  infusion  as  of  higher  nutritive  value 
than  the  article  from  which  it  is  prepared,  I  shall  set  down  this  drink 
as  equal  to  28^  lbs  of  hay.  The  allowance  of  milk  was  stopped  48 
days  after  the  weaning. 

A,  B,  and  C  were  kept  on  their  respective  rations  for  95  days. 
The  three  were  kept  for  the  first  18  days  on  milk  entirely,  during 
which  it  was  calculated  that  each  had  had  from  the  mother  337 
pints     Here  are  the  rations  in  a  tabular  and  comparative  manner. 


A. 

On  the  usual  allowance. 

B. 

On  a  reduced  allowance  of 

mUk. 

0. 

On  hay-tea. 

B 

1 

il 

ft 

If 

Milkinplnta. 

Hay  or  an 
equivalent. 

Food,  94  days.. . 

Suckling,  18  days 

Days  112 

1460 
348 

1_8^ 

lbs. 
374 

"874 

Food,  95  days... 
Suckling,  18  days 

Days  113  

1216 

848 

1564 

lbs. 
896 

896 

lbs. 
Food,  95  days...   232  591 
Suckling,  18  days  848j  . . 

Days  118 1  580'  591^ 

37 


438  REARING   CALVES. 

It  would  have  been  desirable  to  have  had  these  three  calves 
weighed  immediately  after  the  termination  of  the  experiment ;  as 
this  was  not  done,  the  results  have  not  the  whole  of  the  precision 
that  seems  desirable.  Nevertheless,  M.  Perrault  from  his  observa- 
tions concludes ; 

Ist.  That  A,  kept  on  miOt  alone,  weighed  at  birth ....  88  lbs. 
At  the  age  of  452  days 771.0 

Total  increase 888.0 

Increase  per  day 1^ 

2d.    That  B,  on  the  reduced  allowance  of  milk 

weighed  at  birth 8a6  lbs. 

At  the  age  of  224  days 404.2 

Total  Increase 820-6 

Increase  per  day 1.4 

8d.  That  C,  on  hay-tea,  weighed  at  birth 111.2  lbs. 

At  the  age  of  101  days — 270.6 

Total  increase 150.4 

Increase  per  day 1.67 

M.  Perrault's  general  inference  is,  that  the  calf  which  had  the  hay- 
tea  ration  grew  more  rapidly  than  either  of  the  other  two  brought 
up  either  on  pure  or  on  dilute  milk.  The  differences,  however,  are 
within  the  limits  of  the  variations  noted  in  animals  that  are  reared 
on  the  same  ration. 

If  we  reduce  the  various  articles  consumed  in  these  experiments 
to  food  of  the  same  nutritive  value — to  hay,  for  example — we  find, 
that — 

A  consumed  In  112  days,  1857  lbs  of  hay* 

B     "     113  "   1137   " 

O     "     118  "   906   "   " 

The  mininum  ration  for  the  maintenance  of  calves,  to  which 
M.  Perrault  comes  from  his  experiments,  differs  little  from  that  which 
we  think  amply  sufficient  at  Bechelbronn  ;  and  our  animals  certainly 
are  not  inferior  to  those  of  Feuillasse.  This  fact  may  be  judged  of 
by  the  following  particulars,  which  I  have  selected  as  affording  the 
elements  of  contrast  with  M.  Perrault's  B  and  C  : 

Sophy  weighed  at  birth 100.1  lbs. 

At  the  age  of  102  days 279.4 

Total  increase 179.8 

Increase  per  day 1.76 

Food  coninmed :  Milk  525  parts,  weighing  684  lbs.— hay  297  lbs. 
Hay 689 

In  all 886 

Rosa  at  birth  weighed 96.8  lbs. 

At  the  age  of  289  days 478.0 

Total  increase 876.2 

Increase  per  day^ 1.58 

This  calf  consmned :  Milk  528  pints,  weighing  684  lbs.— hay  297  lb& 
Hay 1778 

In  all 2070 

•  Milk  must  be  regarded  in  the  light  of  forage,  so  that  its  equivalent  should  be 
•Uted.    Assuming  milk  to  consist  of  12.61  dry  matter,  and  8T.89  water,  1  find  by 


REARING    CALVES, 


439 


Without  calling  in  the  assistance  of  hay-tea,  consequently,  by 
bringing  up  on  milk  for  seven  weeks,  and  giving  forage  as  soon  as 
possible,  it  is  obvious  that  we  obtain  results  as  fully  as  good  as  those 
of  M.  Perrault. 

I  have  said  that  it  was  during  the  period  when  calves  are  suck- 
ing, or  receiving  a  regular  allowance  of  milk,  that  the  increase  of 
weight  was  most  rapid.  As  the  animal  approaches  the  term  of  its 
complete  development,  the  weight,  in  an  equal  interval  of  time, 
increases  at  a  progressively  diminishing  rate ;  but  from  the  data 
which  I  have  collected,  but  which  are  not  very  extensive,  it  appears 
that  the  increase  is  very  regular  until  the  Ml  growth  is  attained. 
From  this  period  the  animal  continues  stationary  if  he  merely 
receives  the  ration  of  maintenance  ;  any  variation  observed  is  purely 
accidental,  and  loss  or  gain  one  day  is  compensated  by  gain  or  loss 
on  another.  The  adult  animal,  which  does  not  lay  on  fat,  thus 
acquires  a  standard  weight,  which  is  preserved  for  a  term  of  years 
unchanged,  until  the  period  of  decrepitude  and  decay  arrives. 

It  is  not  unimportant  to  ascertain  the  progressive  increase  in 
weight  of  cattle ;  the  balance  is  a  means  which  the  breeder  and 
feeder  ought  not  to  neglect ;  it  is  a  powerful  check  upon  his  ser- 
vants, and  a  sure  tell-tale  in  regard  to  the  state  of  the  stock  at  any 
moment.  A  conscientious  herdsman  is  a  most  precious  person  on  a 
farm ;  but  the  more  I  study  breeding  and  feeding,  the  more  I  am 
satisfied  that  the  most  trustworthy  agent  of  all  is  the  balance.  Fre- 
quent weighings  are  necessary,  in  order  to  keep  a  regular  account 
of  the  state  of  the  cow-houses.  I  here  append  such  absolute  obser- 
vations as  I  have  made  on  the  increase  of  weight  in  horned  cattle, 
with  an  expression  of  regret  that  I  have  not  been  able  to  present  my 
reader  with  more  numerous  data.* 


Names  of  Beasts. 


Weight  at  Age  when  Weight  at  Increase 
birth       weighed,  this  time,  per  diem 


Victoria . . . 

Ditto  

Susan 

Ditto 

Gallop  . . . . 

Ditto 

Ditto 

Schwartz.. 

Sophy 

Migaonne.  • 

Ditto 

Margot  ..• 

®itto 

Ditto 

James 

Ditto 

Ditto 


lbs. 
82 

80 


Davs. 

56 

156 

168 
168 

82 
164 
264 

88 
102 


108 
190 
290 
119 
201 
801 


lbs. 
180 
288 
1T6 
270 
178 
254 


254 

216 
812 
224 

804 
482 
216 
284 
452 


lbs. 
1.98 
1.45 
1.55 
1.26 
1.21 
1.48 
1.59 
1.47 
1.76 
1.84 
1.56 
1.88 
1.56 
1.88 
1.25 
1.07 
1.82 


Under  a  year  old. 


direct  analysis  that  100  of  this  dry  matter  contains  40  of  azot« :  so  that  100  of  milk 
contains  0.50  azote.  This  shows  that  280  of  milk  are  required  to  replace  100  of  good 
meadow  hay,  containing  150  azote. 

*  As  the  weights  were  merely  relative,  I  have  neglected  the  fractions  in  turning 
the  French  Kilogramme  into  avolrd.  pounds.  I  have,  however,  given  the  true  inora- 
toents  of  weights  per  diem. — Eno.  Ed. 


440 


INCREASE    OF    WEIGHT   OF    STOCK. 


Karnes  of  Beasts. 


Weight  at!  Age  when 

Weight  at 

Increase! 

birth,     jweighed. 

this  time. "per  diem. 

lbs. 

Days. 

lbs. 

lbs. 

88 

270 

1.86 

229 

878 

1.40 

M 

829 

588 

1.49 

88 

239 

430 

1.58 

90 

2T5 

570 

1.91 

(( 

867 

782 

1.98 

" 

436 

880 

2.00 

89 

465 

972 

2.09 

u 

547 

1080 

2.00 

90 
100 

730 
811 
796 

976 
1074 
1740 

184 
1.84 
2.26 

98 

1009 

1602 

1.65 

Petrel. 
Ditto . . 
Ditto.. 


Stern 

Ditto 

Diito  

Chastel 

Ditto 

Eichaas 

Ditto 

Castor,  2d  bull. 
Castor,  1st  bull 


From  1  to  8  yrs.  old 


Become  fat,  killed. 
Ditto. 


Byway  of  pendant  to  these  results,  I  give  two  series  of  weighings, 
one  of  which  has  reference  to  the  increase  of  weight  of  a  heifer,  on 
which  I  made  a  number  of  consecutive  observations  ;  the  other  was 
undertaken  with  a  view  to  ascertain  the  variations  which  milch-kine, 
aged  more  than  three  years,  may  experience  : 


Dates 
heifer  weighed. 

S.pt.5..... 

"  23 

Weight. 

lbs 

...869.8) 

..874.0  f 

...893.8 

Gain  between  one 
■weighing  M  another. 

lbs. 

42 

19.8 
85.2 

Time 
elapsed. 

Days. 

8 

14 
41 

Increase 
in  34  hours.         Bemarks. 

1  40  Fed  with  hay 

^•*"  roots. 

141 

Nov.  8 

...429.0 

0.85 

"  28 469.4 

Jan.  29 650.0 

Apl.21 678.4 

July  9 884.4 

Aug.  8 950.4 


40.4 

80.6 

128.4 

206.0 

66.0 


79 


L21 

1.82 

1.60  Was  fed  on  green 

2.48  clover  at  discretion 

2.64 


TABLE  OF  MILCH-KINE  THEEE  YEAE8  OF  AGE  AND  UPWAED8. 

Ist  3d  Interval  between    Diffr'cea 

Names.  Ago.  weighing,  weighing.  Difference,  the  weighings,    per  day. 


Esmeralda 8 

Orphan 3 

Galatea  6 

Gitana  6 

Hannchen  7 

Paysanne  7 

Eaffalea 8 

Prima  Donna  8 

Formosa 9 

Belle  et  Bonne 11 


lbs.  avoir. 
1445 
1815 
1540 
1820 
1100 
1449 
1672 
1784 
1573 
1846 


lbs.  avoir. 
1555 
1434 
1894 
1386 
1236 
1540 
1727 
1654 
1601 
1287 


110 
119 
146 
66 
186 
91 
65 


59 


Days. 


lbs. 
+  1.8 

+  1.6 
-1.7 
+  0.8 
+0.8 
+1.1 
+0.6 
-1.6 
+0.4 
-0.6 


Taking  the  preceding  numbers  as  the  authority,  and  until  we  have 
a  larger  number  of  weighings,  I  think  we  may  conclude  that  the 
living  weight  of  cattle  of  the  Swiss  breed  increases  by  the  follow- 
ing quantities  per  diem  : 

During  the  period  of  suckling  at  the  rate  of  2.4  lbs. 

Under  three  years 1.6 

Above  three  yearn 0.8 

The  increase  of  weight  of  growing  animals  depends  much  on  the 
kind  of  food  they  have  ^  and  it  is  matter  of  great  moment  to  know 
the  precise  amount  of  fodder  which  neat  cattle  require  in  order  to 
thrive.  Those  who  have  treated  of  it  specially,  are  as  far  from 
being  agreed  as  to  the  proper  ration ;  and  then  many  who  have 
specified  the  kind  and  quantity  of  the  food,  have  neglected  the  ages 


ALLOWANCE    TO    CATTLE.  441 

the  absolnte  weights,  the  amount  of  labor  required,  and  the  milk  ob- 
tained from  the  animals.  It  is  subject  of  simple  observation,  that  an 
animal  of  great  size,  all  things  else  being  equal,  will  require  a  larger 
quantity  of  forage  than  another  of  less  bulk. 

Once  the  allowance  of  food  is  well  established,  it  is  greatly  to  be 
desired  that  it  be  continued  with  the  greatest  regularity.  Nothing 
is  more  injurious  to  cattle  than  stinting.  Still  there  is  a  term  in 
every  year  when  the  live  stock,  or  some  portion  of  them,  at  least, 
are  almost  necessarily  stinted  in  their  food  ;  in  the  depth  of  winter 
the  animals  that  are  not  put  up  to  fatten,  consume  little  or  nothing 
but  straw.  At  this  season,  consequently,  the  stock  fall  off  consider- 
ably in  flesh,  in  strength,  and  in  the  milk  they  give ;  and  when  the 
loss  has  been  very  great,  the  animals  are  sometimes  too  far  gone  to 
recover  when  the  spring  has  come  round.  This  state  of  things  is 
greately  to  be  deplored,  and,  indeed,  ought  to  be  viewed  as  most  pre- 
judicial ;  it  will  be  altogetJier  impossible  to  advance  the  economy  of 
neat  cattle  to  the  point  of  perfection  which  it  is  fitted  to  attain,  until 
means  are  taken  to  secure  every  portion  of  the  stock,  at  every  period 
of  the  year,  a  suflSciency  of  properly  nutritious  food.  Happily,  with 
the  progress  of  agriculture,  this  condition  is  becoming  every  year 
more  and  more  easy ;  the  introduction  of  roots,  (turnips  and  mangel- 
wurzel,)  and  of  tubers,  (potato,)  into  the  routine  of  every  farm  that 
is  respectably  managed,  supplies  a  fodder,  through  the  whole  of  the 
winter,  that  is  equivalent  to  the  grass  and  other  green  meats  of 
spring  and  summer. 

1»haer  fixes  at  13  lbs.  the  quantity  of  hay  per  diem  which  a  cow 
requires  for  her  maint;enance  in  perfect  condition ;  and  if  the  animal 
be  in  milk,  he  allows  as  many  as  firom  22  to  33  lbs.  But  the  ration 
must  vary,  as  I  have  said,  with  the  weight  of  the^animal.  M.  Per- 
rault  states  27  lbs.  as  the  allowance  for  a  milch-cow  weighing  about 
880  lbs. ;  he  having,  in  his  experience,  found  that  an  animal  in  milk 
required  about  6i  lbs.  of  hay  for  every  220  lbs.  of  living  weight. 
Pabst,  who  paid  great  attentioL  to  the  feeding  of  cattle,  admits,  that 
for  the  ordinary  allowance  of  an  ox  doing  nothing,  or  of  a  cow  which 
is  dry,  3.85,  or  upwards  of  3f  lbs.  of  hay,  are  required  for  each  220 
lbs.  of  carcass  weight ;  4.4,  or  about  M  lbs.,  if  the  animal  be  a 
draught-ox  ;  and  6.6,  or  upwards  of  6i  lbs.,  if  it  be  a  milch-cow. 

The  inquiries  which  I  have  made  into  this  subject  have  led  me  to 
conclusions  somewhat  different ;  from  which  I  infer,  that  the  rela- 
tion between  the  weight  of  the  living  animal  and  the  necessary  fod- 
der is  not  an  invariable  quantity.  A  very  large  ox  or  cow,  relatively 
to  its  weight,  requires  less  food  than  an  animal  of  smaHer  dimensions. 
And  this  circumstance  is  a  grand  argument  with  those  breeders  who 
are  in  favor  of  very  large  cattle ;  they  saw  that  if  a  large  ox  con- 
sumes more  food  than  a  small  one,  still  the  increase  of  consumption 
is  by  no  means  in  the  ratio  of  the  increase  of  weight. 

The  milch-cows  at  Bechelbronn  have  no  more  than  33  lbs.  of  hay 
per  head  per  diem,  or  the  equivalent  of  this  quantity  of  forage.  But 
the  smallest  creature  on  the  farm,  at  the  time  my  experiments  were 
made  did  not  weigh  less  than  1110  lbs.  '79  stone,  4  lbs.) ;  the  relor 


442 


FEEDING ALLOWANCE. 


tion  of  tlie  livin*  weight  to  the  food  being,  therefore,  as  100  is  to 
2  73,  say  2|. 

The  largest  cow,  again,  weighed  1784  lbs.,  (127  stone  4  lbs.,)  so 
<^at  the  relation  is  here  as  100  is  to  1.85,  or  1  JJths.  The  average 
relation,  taking  the  whole  of  the  cows  in  the  stable,  came  out  as  100 
13  to  2.25 ;  in  other  words,  for  every  100  lbs.  of  carcass  weight, 
24  lbs.  of  meadow-hay  per  day  had  to  be  allowed. 

It  thus  appears,  from  these  inquiries,  that  growing  animals  require 
more  food  relatively  to  their  weight  than  when  they  are  adult.  The 
young  animals,  upon  which  I  made  my  observations,  were  from  5  to 
20  months  old ;  and  for  this  age  I  found  that  for  every  100  of  living 
weight  3.08,  or  upwards  of  3|  lbs.,  of  hay  were  required.  The  fol- 
lowing table  will  give  my  conclusions  at  a  glance : 


s- 

5 

•« 
U 

11. 

1! 

1 

1 

a 

So 

1^ 

Average  age 
of  the  several 

m 

ii 

8^1 

BXKABES. 

i 

5 

animals. 

II 

1^- 

-J 

107 
119 

lbs. 
418 

lbs. 
143 

months,   days. 
8         26 

lbs. 
209 

lbs. 
7.15 

lbs. 
8.48 

In  February 

8     126 
*  i  130 

434 

14.7 

4          6 

242 

7.85 

8.06 

ditto. 

5     205    ^ 

170 
15S 

1267 

86.0 

6          9 

811.8 

18.0 

2.89 

Jaly. 

116    J 

163 

11.0 

5         10 

297.0 

5.5 

8.70 

February 

206 
828    ^ 
290 

9.8 

6         28 

861.4 

465 

2.58 

Septem. 

289 
252 
289    J 

2479 

66.0 

9           6 

495.8 

88.0 

2.66 

July. 

841     ^ 

808 

302 

2586 

62.7 

9         18 

607.8 

81.86 

2.47 

ditto. 

265 

252 

804 

22.0 

10 

627.0 

11.0 

8.60 

February 

871 

19.1 

18          6 

650.0 

9.56 

8.48 

ditto. 

748 
488 

2068 
B  perc 

62.7 
ent  of  li 

80          6 

ving  weight... 

1027.0 

81.85 

8.06 

dltta 

i 

A.verag 

8.08 

In  the  course  of  the  experiments,  the  calves  were  kept  on  good 
meadow-hay,  allowed  them  at  will,  according  to  our  usual  custom, 
the  hay  that  was  put  into  the  crib  once  a  day  was  weighed,  and  an 
account  was  kept  and  deducted  of  any  that  had  been  left  of  the  pre- 
vious day's  allowance.  The  length  of  time  durmg  which  each  sev- 
eral experiment  was  continued,  varied  from  2  to  13  days;  and  I  have 
thought  it  right  to  indicate  the  season  of  the  year,  lest  that  should 
have  any  influence.  To  sum  up,  then,  it  may  be  said,  that  for  every 
100  of  living  weight  neat  cattle  require ; 


FEEDING SALT.  443 

For  simple  snetenance  (Pabst) 0.75  or  i  lbs.  meadow-hav. 

"When  laboring  CPabst)  2.0  "  " 

When  in  milk,  (Pabst) 8.0  "  •' 

"    fPerrault) 8.12  «  " 

"              "    (Boussingault,  large  cows).  8.78  "  " 

Growing  rapidly  [Boussingault] a08  **  •* 

The  forage  ought  to  be  given  to  cattle  with  great  regularity,  and 
care  should  be  taken  that  they  do  not  eat  too  hastily.  Grenerally 
speaking,  they  have  their  allowance  three  times  a  day,  constituting 
so  many  meals,  which,  however,  are  well  divided,  the  whole  quan- 
tity for  each  meal  not  being  placed  before  the  animal  at  once.  This 
precaution  is  particularly  necessary  when  the  allowance  consists  of 
green  fodder.  The  watering  should  take  place  in  the  intervals  be- 
tween meals,  the  animals  being  driven  to  the  trough  night  and 
morning ;  though,  when  the  heat  is  excessive,  it  is  better  to  water 
them  three  times  a  day.  The  water  ought  to  be  of  good  quality, 
though,  if  it  have  no  deleterious  substance  dissolved  in  it,  cattle 
seem  to  make  no  objection  to  that  which  is  turbid,  and  which  can- 
not, we  should  think,  be  very  palatable.  Our  cattle  are  watered, 
during  a  part  of  the  year,  with  water  from  a  shaft  pierced  through 
a  highly  argillaceous  soil.  Cattle  seem  to  dislike  excessively  cold 
water ;  they  then  drink  as  little  as  possible.  The  cattle  in  the  great 
South  American  plains,  drink  water  at  a  temperature  of  from  85°  to 
970  F.  In  Europe,  the  best  water  in  point  of  temperature  in  winter 
is  that  of  a  deep  well. 

Every  one  is  familiar  with  the  taste  which  herbivorous  animals 
show  for  salt,  and  this  is  one  of  the  articles  which  is  advantageously 
made  to  enter  into  the  ration  when  its  price  is  not  too  high.  In 
France,  it  is  absolutely  necessary  to  use  the  article  with  extreme 
parsimony — a  circumstance  which  I  much  regret,  and  which  I  can- 
not but  view  as  prejudical  to  rural  economy  : — [in  England,  where 
the  odious  salt-tax  has  been  got  rid  of,  salt,  of  the  most  beautiful 
quality,  is  one  of  the  cheapest  of  all  manufactured  substances.]  I 
know  that  many  feeders  do  not  think  salt  indispensable ;  but  their 
authority  is  opposed  by  that  of  some  of  the  highest  names  in  Ger- 
many and  England,  and  my  own  mind  has  long  been  made  in  regard 
to  the  value,  to  the  excellent  effects  of  this  substance.  I  ascertain- 
ed, for  instance,  that  milch-kine,  though  they  would  not  do  upon 
potatoes  alone,  throve  very  well  when  they  had  from  two  or  two  and 
a  quarter  ounces  of  common  salt  added  to  the  ration.  A  celebrated 
English  breeder,  Mr.  Curwen,  recommends  about  3|  ounces  of  salt 
to  be  given  daily  to  cows  and  heifers  in  calf,  and  to  draught-oxen, 
and  something  less  to  fatting  oxen,  to  young  animals,  and  to  calves.* 

The  high  price  of  salt  in  France  does  not  allow  us  to  be  so  liberal 
at  Bechelbronn ;  yet  we  make  a  distribution  of  the  article  three 
times  a  week,  and  in  quantities  which  bring  the  allowance  to  some- 
thing more  than  about  an  ounce  and  a  half  per  day.  By  way  of 
eking  out  the  allowance  of  saline  matter,  we  further  supply,  from 
time  to  time,  a  quantity  of  Glauber  salt,  which  comes  in  all  to  rather 

♦  Sinclair,  Agriculture. 


444  MILCH-KINE. 

more  than  half  an  ounce  per  head  per  diem.  The  use  of  this  salt, 
sulphate  of  soda,  has  long  been  common  in  Alsace,  and  also  on  the 
other  side  of  the  Rhine ;  and  its  effect  on  the  health  of  horses  and 
of  sheep,  as  well  as  of  horned  cattle,  has  been  reconized  as  highly 
advantageous.  In  Wurtemberg,  the  horses  have,  very  commonly, 
725  grains,  neat  cattle  463  grains,  sheep  305  grains,  and  swine  250 
grains  of  Glauber  salt  twice  a  week.* 

Salt  appears  to  be  more  especially  useful  in  hot  weather  and  in 
warm  climates.  In  the  steppes  of  South  America,  it  is  held  by  the 
llama  keepers  as  an  axiom  that  cattle  cannot  live  without  salt. 
Wherever  a  flock  thrives  particularly  well,  it  may  be  averred  d 
priori,  that  there  is  a  salado  there,  a  salt  lick  of  the  North  Ameri- 
cans, or  place  where  there  is  a  salt-spring.  In  the  savannas  that 
are  without  saline  springs,  the  herdsmen  make  a  distribution  of  salt 
every  day.  On  the  plateau,  or  table-land,  of  Nueva  Granada,  com- 
mon salt  is  replaced  with  Glauber  salt,  as  in  Alsace  and  Wurtem- 
burg,  and  I  may  say,  that  it  was  matter  of  much  interest  to  me  to 
find  the  same  custom  prevailing  on  the  table-lands  of  the  Andes 
as  upon  the  banks  of  the  Rhine. 

§   II.    MILCH-KINE. 

I  have  akeady  had  occasion  to  say,  that  the  signs  by  which  the 
qualities  of  kine  as  milkers  were  sought  to  be  appreciated,  are  some- 
what deceitful.  Still,  I  am  far  from  denying  that  practice  and  ex- 
perience do  not  enable  many  persons  to  pronounce  with  some  cer-. 
tainty  upon  this  particular.  The  power  of  doing  so,  however,  is  in 
some  sort  the  peculiar  privilege  of  him  who  possesses  it ;  at  least,  I 
have  seen  all  the  general  rules  that  have  been  laid  down  on  the  sub- 
ject fail ;  I  have  seen  cows  of  the  most  opposite  conformations 
equally  productive.  I  have  also  said,  that  race  or  descent  had  much 
to  do  with  this  quality  ;  the  heifer  that  comes  of  a  mother,  a  good 
milker,  will  be  very  likely  to  turn  out  a  good  milker  also.  The 
legitimate  way,  therefore,  of  obtaining  a  good  race  of  milch-kine,  is 
to  breed  them  from  a  stock  that  is  already  noted  in  this  respect.  At 
the  time  of  my  penning  these  lines,  there  are  two  animals  on  the 
farm  that  are  remarkable  as  milch-kine :  one  is  a  tall,  unseemly 
animal,  the  bones  projecting,  and  altogether  thin  and  miserable  ;  the 
other  is  a  small  cow,  with  rounded  outlines  everywhere,  the  bony 
frame  but  little  conspicuous ;  her  skin  soft,  her  hair  sleek  and  fine. 
Nevertheless,  these  two  animals  have  one  character  in  common — 
the  udder  is  of  extraordinary  size. 

We  ought  not  to  be  hasty  in  judging  of  the  value  of  a  milch-cow 
after  the  first  calf ;  age  has  great  influence  on  the  secretion  of  milk. 
It  is  generally  allow^  tliat  a  cow  does  not  attain  to  her  maximum 
capacity  of  yielding  milk  until  she  has  passed  her  sixth  year. 

With  regard  to  the  means  we  have  of  judging  of  the  age  of  a  cow, 
they  are  principally  derived  from  the  horns.  The  teeth  do  not  af- 
ford us  any  indication,  as  in  the  horse  and  sheep.     In  the  ox,  about 

♦  Communicated  by  M.  Schattenmani^ 


MILCH-KINE. 


445 


the  fifth  year,  there  is  a  ring  formed  about  the  root  of  each  horn ;  in 
the  cow,  this  ring  makes  its  appearance  after  the  first  calving,  and 
from  this  epoch  there  is  a  new  ring  formed  each  year,  which  pushes 
on  the  former  one.  In  aged  animals  these  rings  have  become 
faint,  and  can  scarcely  be  counted.  It  is  also  evident  that  the  horna 
which,  in  early  life,  were  thicker  at  the  base,  and  tapered  gradually 
towards  the  tips,  about  the  ninth  or  tenth  year  of  the  animal's  life 
present  an  opposite  conformation ;  they  exhibit  a  kind  of  constriction 
nt  the  roots.  The  depression  above  the  eye  increases  with  age,  and 
the  false  hooves  become  long  and  often  bent. 

Thaer  reckons  that,  one  with  another,  in  well-regulated  establish- 
ments, cows  will  continue  in  milk  for  about  280  days,  and  yield  in 
all  about  2265  pints,  or  283  gallons.  But  it  is  certain,  that  the  yield- 
ing of  a  cow  varies  greatly  with  circumstances,  race,  age,  climate, 
and  individual.  The  cows  that  graze  at  liberty  in  South  America, 
do  not  give  more  than  about  three  pints  of  milk  per  diem  ;  which,  as 
it  is  almost  wholly  used  in  bringing  up  the  calf,  the  dairy  is  there 
of  very  little  importance.  In  established  farms,  a  cow  is  reckoned 
to  yield  about  40  lbs.  of  cheese  per  annum.  Mr.  Curwen  estimates 
the  quantity  of  milk  at  6580  pints,  or  822  gallons,  per  cow;  M.  Per- 
rault  states  it  at  but  2992  pints,  or  374  gallons ;  and  Mr.  Low  gives 
the  quantity  at  5994  pints,  or  749  i  gallons.  The  differences  between 
these  several  quantities  are  obviously  enormous,  and  can  scarcely 
be  reconciled  with  any  conceivable  diversity  of  circumstances. 
They  are  probably  connected  with  the  method  taken  to  ascertain  the 
quantities. 

The  following  table  comprises  the  whole  of  the  statements  with 
which  I  am  acquainted. 


ObservationB, 


France:  La  Fenillasse  [Aln]:P.  de  Jotemps. 

Lompries  [Ain  |         iD'Angeville. 

Eoville  [Meurthe] |Do  Dombasle. 

Lyonnais  [montagnes] .  jGrognier. 
Bachelbronn  [Bas-Rhin]  Eel  «fc  Boussing'! 

England  Low 

Do.        •     ICurwen . 

Belcium :  Antwerp.  iSchwertz. 

Do  jSchwertz. 

Ilolland :  Low  countries —  Schwertz. 

Do...    jAiton. 

Campine  'Schwerts. 

Saxony :  Meissen    jSchweitzer. 

Altenburg,  jSchmalz. 

Austria :  Carinthia Burger. 

Prussia:  Moeglin iThaer. 

Neighborhood  of  Berlin  Thaer. 

Switzerland    iD'Angeville. 

Hoflfwyll iD'Angeville. 


lbs. 
88C 
605 


lbs.  pts. 
27.52992 
14.8:1610 
22.0!2492 

"  1284 
88.0     " 

"  5994 
28.66580 
27.24495 
27.239671 

"  ;8400 

"  i7066; 

"  9313^ 
18.6  2687 
80.88412 

"  J2752 
22.02648 
27.58004 


pts 
8.2 
4.4 
5.9 
8.5 
(( 

16.2 

17.8 

12.8 

10.9 

9.2 

19.4 

26.5 

17. 

9.2 

7.5 

7.2 


Cows 
In  the  house. 

Do. 

Do. 
ni-fed  in  winter 

Do. 
Do. 

Do.  niouse. 
At  grass  &  in  the 
In  house,  winter 


Kept  in  house. 

Well  fed. 
Kept  in  house. 


a2        Do. 

13201  88.514685;  12.8  Well  fed. 


At  Bechelbronn  we  have  seven  cows  whose  allowance  per  head 
is  33  lbs.  of  hay  per  diem.    The  milk  is  measured  night  and  monv 
38 


446  MILCH-KINE. 

mg,  and  the  quantity  given  by  each  cow  is  particularly  noted.  The 
herd  consisted  of  Raflfalea,  8  years  old,  whose  milk  failed  the  21st  of 
April,  and  reappeared  the  18th  of  June  without  her  having  calved ; — 
La  Paysanne,  7  years  old,  whose  milk  ceased  the  21st  of  February, 
and  she  calved  the  29th  of  April ; — Prima  Donna,  8  years  old  :  milk 
stopped  February  19th,  calved  December  5th ; — Formosa,  9  years 
old  :  ceased  milking  1st  April,  calved  2d  June  ; — La  Gitana,  6  years 
old :  ceased  milking  30th  September,  calved  9th  November  ; — Grala- 
tea,  6  years  old :  ceased  milking  9th  July,  calved  2d  October : — Belle 
et  Bonne,  Hi  years  old  :  ceased  milking  the  15th  February,  calved 
3d  April.  These  seven  cows  gave  in  the  course  of  the  year,  neg- 
lecting fractions,  30576  pints,  or  3822  gallons  of  milk.  In  the  month 
of  January,  in  round  numbers,  1870  pints;  in  February,  1260  pints; 
March,  1260  pints ;  April,  1657  pints ;  May,  2527  pints ;  June,  3726 
pints ;  July,  4180  pints,  August,  3661  pints ;  September,  2913 
pints ;  October,  2622  pints  ;  November,  2540  pints ;  December, 
2360  pints ;  having,  one  with  another,  given  546  gallons  of  milk, 
and  milked  on  an  average  302^  days  each ;  the  entire  herd  having 
milked  during  2118  days,  and  the  average  quantity  yielded  by  each 
cow  having  been  14.6  say  14^  pints  for  every  day  she  was  in  milk  ; 
the  quantity  for  each,  day  of  tne  year  amounts  to  11.9,  say  10  pints. 

June,  July,  and  August  are  obviously  the  months  most  productive 
of  milk,  during  which  the  cows  had  scarcely  any  other  food  than 
clover.  The  average  quantity  for  these  months  was  undoubtedly 
raised  from  three  of  the  cows  having  calved  in  March,  April,  and 
May,  so  that  these  were  severally  giving  their  largest  measures  dur- 
ing the  three  summer  months. 

It  may  be  enough  to  state,  that  the  largest  quantity  of  milk  is  ob- 
tained in  the  course  of  the  three  first  months  after  calving  ;  the  pro- 
duce then  will  amount  to  18,  20,  and  even  24  pints  per  day,  while 
the  mean  quantity  during  the  whole  time  of  milking  will  very  little 
exceed  12  pints. 

The  observations  for  the  year  1842,  which  I  referred  to  some 
short  way  back,  showed  a  mean  of  14.6,  say  14^  pints  of  milk  for 
each  cow.  But  in  the  mode  of  reckoning  pursued,  there  were 
sources  of  error,  which  have  been  avoided  in  the  estimates  just 
given.  The  only  mode  of  securing  accurancy  of  result  is  to  take  the 
quantity  of  milk  yielded  by  each  cow  between  the  period  of  calving 
one  year  to  the  same  event  the  following  year.  This  mode  of  reck- 
oning gives  the  quantity  13  pints  per  day  for  each  cow,  which  I  am 
disposed  to  adopt  as  the  standard  for  the  Swiss  breed,  fed  with  33 
lbs.  of  good  meadow-hay,  or  an  equivalent  of  wholesome  roots,  &c. 
I  am  also  disposed  to  look  upon  310  as  the  mean  number  of  days 
during  which  a  cow  will  give  milk  after  calving. 

We  sometimes  see  quantities  of  milk  mentioned  as  given  by  par- 
ticular cows  that  are  truly  surprising,  and  that  seem  even  calculated 
to  excite  suspicion  of  the  veracity  of  the  reporters.  Some  have 
spoken  of  cows  that  gave  44  and  52 J  pints  of  milk  a  day  for  several 
months.  M.  Crud  says  that  cows  of  great  size  indeed  have  even 
given  as  many  as  70.4  pints  in  twenty-four  hours  ;  and  Thaer  goes 


MILCH-KIN  E.  447 

still  farther  when  he  states  that  persons  worthy  of  every  credit  say 
they  have  seen  cows  in  first-rate  pastures,  which,  at  the  height  of 
their  milking  time,  produced  as  many  as  from  74  to  82^  pints  of  milk 
in  the  twenty-four  hours.  Such  a  flux  of  milk  can  only  be  very  tem- 
porary, and  indeed  must  occur  but  very  rarely.  The  herdsmen  at 
Bechelbronn  have  often  diverted  me  with  tales  of  such  marvels 
but  since  I  have  accurately  guaged  the  dairy  produce  of  the  farm,  J 
have  met  with  nothing  which  would  lead  me  to  credit  their  reality 
We  have  had  cows  indeed  which  have  given  26^,  and  even  31^ 
pints  a  day  for  several  weeks  ;  but  these  are  still  very  far  from  the 
quantities  which  have  been  mentioned  to  me. 

Good  feeding  is  undoubtedly  required  in  order  that  cows  may  pro- 
duce milk  abundantly  ;  but  I  believe  that  the  influence  of  particular 
kinds  of  forage  on  the  production  of  milk  is  often  greatly  exaggera- 
ted. Each  breeder  or  feeder  seems  to  have  his  own  favorite  article, 
however,  so  that  there  is  nothing  like  uniformity  among  them  ;  with 
one  it  is  the  carrot  that  is  in  the  ascendant ;  with  another  it  is  the 
beet  that  is  supreme  ;  there  is  no  root,  in  fact,  which  has  not  alter- 
nately had  its  apologists  and  detractors.  The  truth  lies  between  the 
extremes  here  as  it  does  in  so  many  other  instances  ;  and  I  am  sat- 
isfied that  each  and  all  the  roots  and  other  articles  of  forage  that  are 
generally  introduced  into  the  rations  of  milch-kine,  are  calculated  to 
produce  abundance  of  good  milk  ;  it  is  only  necessary  that  the  sub- 
stances be  allowed  in  ample  quantity,  that  no  mistake  be  committed 
in  regard  to  the  nutritive  equivalents  of  the  several  articles.  I  do 
not  hesitate  to  add,  that  the  opinions  of  the  generality  of  farmers  and 
dairymen  on  the  subject  are  based  on  observations  which  are  always 
more  or  less  imperfect. 

It  is  but  a  few  years  ago  that  a  series  of  experiments  were  under- 
taken at  Bechelbronn,  with  a  view  to  ascertain  whether  the  particu- 
lar nature  of  each  of  the  several  articles  consumed  by  milch  kine 
influenced  the  quantity  or  chemical  constitution  of  the  milk  in  any 
appreciable  manner.  The  purpose  of  these  inquiries  being  purely 
practical,  having  been  undertaken  with  as  pecial  eye  to  the  dairy 
and  its  produce,  the  inquiry  was  confined  to  the  articles  that  are 
usually  given  to  cows  with  us.  These  necessarily  vary  with  the 
season,  but  I  have  already  said  that  the  dole  to  each  head  is  equiva- 
lent to  33  lbs.  of  meadow-hay,  which,  indeed,  always  enters  in  con- 
siderable quantity  into  the  ration,  whatever  else  be  given,  unless, 
indeed,  the  animals  are  exclusively  upon  green  meat,  when,  of  course, 
the  use  of  every  thing  else  is  suspended.  In  winter  the  hay  is  mixed 
with  beet,  potatoes,  turnips,  or  Jerusalems.  In  spring  the  hay  is 
gradually  replaced  by  green  fodder,  which  in  the  first  instance  is  rye 
cut  green,  and  by  and  by  clover.  The  experiments  which  I  shall 
now  detail  were  made  upon  a  cow  which  had  calved  two  hundred 
days,  and  was  again  pregnant. 

1st  EXPEKIMENT. 

200  DAYS  AFTER  CALVING. 

The  cow  fed  on  hay  alone  gave  65.42  pints  of  milk  in  the  courae 
of  seven  days,  or  9.34  pints  per  day.    This  milk  consisted  of: 


MS                                               MILCH-KINE. 
Caseum 

l^'ofmii:::::::v::;;:.;-  t-vsom^i^a 

Ash  of  caseum 

Water 87.7 

100.0 

2d  EXPERIMENT. 

207    DAYS   AFTER   CALVING. 

Fea  with  turnips  and  cut  straw,  (the  ration  consisting  of  turnips 
equal  to  29.7  lbs.,  and  straw  equal  to  3.3  lbs.  of  hay,)  the  same  cow 
gave  in  the  course  of  eight  days  84.4  pints  of  milk,  or  10.5  pints  per 
day.    The  composition  of  this  milk  was  : 

Caaeum 8.0  \ 

g?r„f  miii;.;.;.;.::;:.:;.:::  l:S[8«ud.M.4 

Ash  of  caseum. 0.2  ) 

Water 87.6 

100.0 
The  animal  discussed  her  provender  with  good  appetite,  but  the 
ration  was  too  large ;  about  11  lbs.  of  the  turnips  being  left  each  day 
unconsumed. 

3d  EXPERIMENT. 

215  DAYS   AFTER  CALVING. 

The  ration  here  consisted  of : 

Field-beet,  an  equivalent  for  29.7  lbs.  of  hay. 
Chopped  straw       "  8.6       " 

In  the  course  of  fourteen  days  the  quantity  of  milk  obtained 
amounted  to  137.6  pints,  or  9.8  pints  per  diem,  and  was  composed 
as  below : 

Caseum 8.4 

»?"«' f  2  y  Solidfl  12.9 

Milk  sugar  6.8  f  '^"""°  ■^*-«' 

Ash  of  caseum O.f 

Water 87.1 


( 


100.0 

4th  EXPERIMENT. 

229  DAYS   AFTER  CALVING. 

The  ration  consisted  of: 

Kaw  potatoes  equivalent  to  29.7  lbs  of  haj. 
Chopped  straw       "  8.6         " 

In  the  course  of  eleven  days  the  cow  gave  96.1  pints  of  milk,  or 
at  the  rate  of  8.7  pints  per  day,  the  fluid  consisting  of: 
Caseum 8.4^ 

a?'J«g;i::::::::::;:.;.v:::.:;»:S[9«''*'»M 

Ash  of  caseum 0.2; 

Water 86.5 

100.0 

The  cow  did  not  do  well  upon  this  regimen  :  she  became  heated, 
and  refused  one-half  the  straw.  In  a  general  way  we  do  not  give 
tubers  to  a  greater  extent  than  is  equivj>^ent  to  one-holf  of  the  allow- 
ance of  hay,  in  which  proportion  cows  d<>  very  well  upon  raw  potatoes. 


MILCH-KINE.  44& 

6th  EXPEKIMENT. 

240  DAYS  AFTER  CALVING. 

The  forage  here  consisted  of  the  full  allowance  of  hay,  or  33  lbs. 
In  the  preceding  experiment  the  milk,  which  had  hitherto  kept  up  to 
from  about  9|  to  10^  pints  a  day,  fell  suddenly  to  little  more  than 
8 J  pints.  To  ascertain  whether  the  fall  was  owing  to  the  potato 
regimen  or  not,  the  cow  was  returned  to  the  ration  of  hay,  mider 
which  in  the  Ist  experiment  the  daily  average  of  milk  was  9.3  pints. 
In  the  course  of  thirty  days  188  pints  of  milk  were  collected,  at  the 
rate  of  6.2  pints  per  day.  The  declension  in  the  quantity  secreted 
consequently  cannot  be  ascribed  to  the  potatoes  which  were  given 
in  the  fourth  experiment. 

6th  EXPERIMENT. 

270   DAYS   AFTEB   CALVING. 

The  ration  here  was  raw  potatoes,  with  salt  and  straw — the  ration 
of  the  fourth  experiment,  with  the  addition  of  about  2^  oz.  of  salt. 
The  animal  ate  this  salted  ration  with  appetite ;  she  also  made  away 
with  the  whole  of  the  chopped  straw,  and  it  agreed  well  with  her  ; 
nevertheless,  the  milk  continued  to  decrease  in  quantity ;  it  had 
failed  oflf  to  5.9,  say  6  pints  a  day. 

7th  EXPERIMENT. 

290   DAYS     AFTER   CALVING. 

In  this  trial  the  ration  consisted  of  Jerusalem  potatoes  equivalent 
to  33  lbs.  of  hay,  under  which  the  milk  may  be  said  to  have  remain- 
ed stationary,  though  it  was  above  rather  than  under  the  6  pints  per 
diem  as  in  the  6th  experiment.     In  composition  it  was  as  follows  : 

Caseum 8.3  ) 

fuTofn„ii-.:-.-.v.v.v.".v..::;:  ti  sond.m 

Ashof  Caseum 0.2  j 

Water 8T.5 

100.0 

The  quantity  of  the  milk  had  obviously  decreased  from  the  first 
down  to  the  two  last  experiments ;  but  its  chemical  constitution 
does  not  appear  to  have  varied  during  the  entire  course  of  the  trials  ; 
the  varied  regimen  has  had  no  influence  on  the  proportions  in  which 
its  several  ingredients  are  encountered.  But  there  was  still  one 
point  to  be  ascertained,  viz. :  whether  the  milk  secreted  very  shortly 
after  the  delivery  differed  from  that  which  was  formed  at  a  period 
remote  from  that  epoch. 

8th  EXPERIMENT. 

A  cow  which  had  calved  twenty-four  dajrs  before,  and,  upon  a 
mixed  regimen  of  hay  and  green  clover,  was  giving  at  the  rate  of 
18.6  pints  of  milk  a  day,  was  brought  under  observation.  Analysis 
showed  this  milk  to  consist  of : 

Caseum 8.0) 

^^o,-;^::::::::::::::::::  II  ^"^^^ 

Ash  of  caseum 0.2  j 

Water 88.8 

100.0 

38* 


450  MILCH-KINE. 

9th  EXPERIMENT. 

35   DAYS  AFTER   CALVING. 

The  same   cow,  upon  green  clover,  was   now  producmg   21.2 
pints  of  milk  a-day,  and  of  the  following  composition  : 

Caseum 8.1  \ 

L-^r  <m«i-.:-.:-.-.v;;;;::::;::  il  [  ^-"-^  '«•" 

Ash  of  caseum 0.8) 

Water 86.8 

100.0 

This  milk  evidently  presents  a  larger  quantity  of  butter  than  ap- 
pears in  any  of  the  preceding  analyses.  But  no  hasty  conclusion 
must  be  drawn  from  this ;  for  the  succeeding  experiments  will  ex- 
hibH  a  change  equally  sudden  in  the  proportion  of  the  fatty  element, 
but  in  a  different  way. 

In  a  second  series  of  experiments  I  set  myself  the  task  of  ascer- 
taining whether  green  fodder  had  any  such  remarkable  influence  on 
the  production  of  milk,  and  especially  of  its  fatty  element,  or  butter. 

1st  EXPERIMENT. 

BEGUN  176  DAYS  AFTER  THE  CALVING. 

The  ration  here  consisted  of  winter  fodder : 

Potatoes  equivalent  to  16.5  lbs.  of  hay. 
Hay  "  16.5    " 

Upon  which  the  cow  had  long  been  kept  though  the  milk  was  only 
measured  during  the  last  six  days.  The  quantity  was  16.3  pints  a 
day,  and  consisted  of ; 


Caseum 8.8) 

f."^T«f  miii-.:;;::;;;.v.v.v.;:;  J:f  [8oud.i&» 

Ash  of  caseum 0.8  ; 

Water 86.6 


100.0 

2d  EXPERIMENT. 

182   DAYS   AFTER  THE   CALVING. 

Mixed  regimen:  Green  clover  equivalent  to  16.5  lbs.  of  hay. 
Hay  "  16.5  " 

Upon  which  the  quantity  of  milk  was  at  the  rate  of  17  pints  a  day. 
3d  EXPERIMENT. 

193    DAYS    AFTER   THE    CALVING. 
Green  meat :  Clover  equivalent  to  88  Iba  of  hay 

Quantity  of  milk,  17.2  pints  a  day,  composed  of. 

Ctoeum 4.0) 

B'^tt«^ 2.2(.g^U^lUI 


Sugar  of  milk 4.7 

Afih  of  caseum  0.8 

Water. 89.7 

100.0 


MILCH-KINE.  451 

The  small  quantity  of  butter  here  induced  me  to  repeat  the  analy- 
sis, but  the  result  came  out  very  nearly  the  same,  the  quantity  being 
still  but  2.35  per  100. 

4th  EXPERIMENT. 

204   DAYS   AFTER   THE    CALVING. 
Green  fodder :  same  quantity  as  before. 
Milk  per  day  13.7  pints,  composed  of : 
Caseum 8.7  ^ 

lugr„fm,,i-.-.;::;:;:::::;:;::ll[s«ua»«-6 

Ash  of  caseum 0.2  ; 

Water 87.4 

100.0 

It  would  therefore  appear  that  fresh-cut  clover  has  no  such  virtue 
as  that  of  increasing  the  quantity  of  milk  given  by  cows.  Under 
the  winter  fare,  in  fact,  the  milk  produced  in  the  course  of  the 
twenty-four  hours  amounted  to  16.7  pints  ;  under  green  clover  it 
was  but  14.9  pints.  It  would  be  a  great  mistake,  however,  as  I 
conceive,  to  ascribe  the  diminution  here  to  the  use  of  the  green 
forage  ;  it  is  due,  I  apprehend,  exclusively  to  the  greater  length  of 
time  that  has  elapsed  since  the  period  of  calving. 

The  chemical  composition  of  the  milk  varied  little,  as  I  have 
already  incidentally  remarked,  in  the  course  of  these  experiments. 
The  differences  in  respect  of  the  caseum,  by  which  let  me  say  I 
understand  the  whole  of  the  azotized  constituents,  the  whole  flesh 
of  the  milk,  rarely  exceed  one  hundredth  part.  The  proportion  of 
the  fatty  element  varies  suddenly,  and,  as  it  seems,  independently 
of  the  various  circumstances  in  which  the  cows  are  placed. 

The  general  inference  from  these  experiments,  then,  is  that  the 
nature  of  the  food  does  not  exert  any  marked  influence  on  the  quan- 
tity and  chemical  constitution  of  the  milk  (I  do  not  now  speak  of 
the  quality  of  the  fluid)  if  the  cows  but  receive  the  proper  nutritive 
equivalents  of  the  several  sorts  of  provender.  It  is  of  great  impor- 
tance to  insist  on  this  point ;  for  it  is  quite  certain,  that  if  the 
weight  of  the  several  rations  be  not  calculated  according  to  that  of 
the  equivalents,  variations  in  the  secretion  of  milk  would  be  forth- 
with conspicuous ;  but  then  these  variations  would  have  the  increase 
or  diminution  of  the  provender  allowed  as  their  cause. 

When  cows  are  kept  through  the  winter  upon  straw  alone,  they 
cease  to  give  milk  ;  but  on  the  return  of  green  forage,  in  the  spring, 
the  secretion  is  restored.  The  re-appearance  of  the  milk  in  this 
case,  however,  is  not  connected  with  the  coming  in  of  the  fresh 
provender,  but  with  the  return  of  plenty  ;  the  animals  are  not  only 
fed,  from  having  been  starved,  but  they  are  more  than  fed ;  they 
have  something  to  spare,  which  their  economy  turns  partly  into  milk. 

In  well-managed  establishments,  where  a  good  system  of  hus- 
bandry secures  an  abundant  supply  of  good  nutritive  provender  to 
the  cattle  during  winter,  the  produce  of  the  dairy  during  this  season 
differs  much  less  from  that  of  the  summer  than  is  generally  supposed. 
I  am  besides  persuaded  that  we  estimate  the  nutritive  powers  of 


452  FATTENING. 

green  forage  at  too  low  a  rate,  and  that  \<'hru  cattle  are  upon  wet 
clover  or  lucern,  they  are  in  fact  much  moie  effectually  nourished 
than  under  ordinary  circumstances. 

If  it  be  true,  as  it  evidently  is,  that  the  quantity  of  milk  produced 
depends  especially  upon  the  absolute  quantity  of  nutritive  food  con- 
sumed, it  is  not  so  with  the  quality  of  the  fluid.  It  is  undeniable, 
that  the  milk  of  spring  and  summer,  formed  upon  green  and  succu- 
lent food,  is  much  more  palatable  than  that  of  the  winter  season ; 
the  butter  is  also  much  finer  and  better  flavored.  The  green  herbs 
of  our  pastures  undoubtedly  contain  volatile  principles  which  are 
dissipated  and  lost  in  the  processes  of  drying  and  fermentation 
which  they  undergo  in  their  conversion  into  hay.  If  chemistry-  be 
powerless  'in  seizing  such  principles,  it  still  informs  us  of  the  possi- 
bility of  introducing  a  variety  of  articles  into  the  food  of  cows 
which  have  the  property  of  communicating  those  qualities  which 
we  prize  in  milk.  In  all  grazing  countries  certain  vegetables  are 
pointed  out  as  giving,  in  the  vulgar  opinion,  a  particular  aroma  to 
the  flavor  of  milk. 

§   III.    FATTENING   OF    CATTLE. 

Under  a  parity  of  circumstances,  feeding  cattle  for  the  butcher 
may  occasionally  be  found  more  advantageous  than  the  dairy  to  the 
farmer.  In  feeding  for  the  market  there  is,  in  the  first  place,  a 
quicker  return  for  the  outlay  than  in  keeping  milch-kine  through 
the  whole  of  the  year.  In  the  first  operation,  the  capital  is  realized 
at  the  end  of  four  or  five  months  ;  that  which  is  employed  in  produ- 
cing milk,  and  butter,  and  cheese,  is  always  lying  out  like  a  sum  at 
interest. 

The  quantity  of  food  requisite  to  bring  cattle  intended  for  the 
butcher  into  condition,  does  not  vary  less  than  that  which  is  required 
to  secure  a  plentiful  production  of  milk.  Thus  the  stature,  the  age, 
the  race  of  the  individual,  and  the  relative  proportions  of  flesh  and 
fat  which  we  would  have  laid  on,  all  imply  varied  doles  of  various 
kinds  of  forage.  The  age  in  especial  has  to  be  considered  ;  for  in 
putting  up  a  young  animal  to  fatten,  we  have  both  flesh  and  fat  to 
form.  This  is  what  always  occurs  in  the  fattening  of  oxen  of  two 
years  old,  and  of  pigs  of  ten  or  eleven  months.  The  increase  in 
living  weight  experienced  at  various  ages,  is  not  equally  owing  to 
accumulation  of  fat ;  this  indeed  may  be  so  in  the  case  of  beasts, 
the  muscular  system  of  which  ha«  already  attained  complete  devel- 
opment, but  it  is  otherwise  with  young  and  still  growing  animals. 

Practice  does  much  in  enabling  us  to  select  the  animals  that  will 
fatten  readily.  In  a  general  way  it  is  well  to  choose  yomi^  animals 
that  have  a  large  chest,  the  body  bulky  and  rounded,  the  ribs  finely 
arched,  the  bones  small,  the  limbs  short,  the  neck  thick  for  its 
length,  the  skin  soft,  pliant,  velvetv  to  the  touch,  and  moveable  over 
the  body,  particularly  over  the  ribs,  the  tail  should  be  scanty,  the 
buttocks  not  deeply  cleft,  but  fleshy — well  breeched,  as  the  phrase 
runs  in  some  districts.    The  look  of  the  animal  should  be  sharp 


FATTENING.  463 

ftnd  bold ;  the  horns  slender,  whitish,  and  rather  transparent.    The 
animal  must  have  been  cut  while  he  was  still  at  the  teat. 

The  celebrated  English  breeder,  Eobert  Bakewell,  succeeded, 
after  a  long  and  troublesome  course  of  experiments,  in  creating  a 
race  of  neat-cattle  and  of  sheep  which  show  themselves  particularly 
disposed  to  take  on  fat.  The  fundamental  principles  established  by 
Bakewell,  after  all  his  experience,  are  these  :  that  smailness  of 
bone,  fineness  of  skin,  and  cylindrical  shape  of  body,  are  the  surest 
indications  in  cattle  of  the  disposition  to  lay  on  fat  readily,  and 
upon  the  smallest  quantity  of  provender.  The  most  striking  features 
in  the  breed  obtained  by  Bakewell,  commonly  known  as  the  Dishley 
breed,  may  be  summed  up  in  the  following  terms  : 

1st.  The  animal  low  on  his  legs. 

2d.  The  back-bone  straight. 

3d.  The  carcass  rounded  and  almost  cylindrical. 

4th.  The  chest  deep  and  large. 

An  ox  is  held  to  have  grown  rapidly  and  well,  when  at  the  age  of 
three  years  he  weighs  from  1016  to  1051  lbs.  avoirdupois,  from  72 
to  75  stone.  The  disposition  to  fatten  young  is  also  a  precious 
quality  in  the  beast  which  it  is  intended  to  bring  for  the  butcher ; 
the  feeder  comes  the  sooner  at  his  return.  Sinclair  thinks,  that  in- 
dependently of  good  constitution,  which  is  indispensable,  this  quality 
is  derived  especially  from  meekness  of  disposition,  from  good  tem- 
per ;  and  as  docility  is  generally  the  result  of  good  treatment  in 
early  life,  young  animals  ought  always  to  be  treated  with  great 
gentleness  and  made  perfectly  familiar. 

The  different  races  do  not  all  yield  meat  of  the  same  quality,  and 
this  quite  independently  of  age.  The  best  meat  has  a  very  decided 
and  characteristic  flavor  after  it  is  dressed,  which  indiffeient  meat 
wants,  or  which  is  replaced  by  a  savor  that  is  disgusting  rather 
than  agreeable.  The  fat  in  the  best  meat,  as  well  as  being  laid  on 
superficially,  is  distributed  through  the  substance  of  the  muscles,  so 
as  to  give  the  flesh  a  marbled  appearance. 

In  fattening  cattle  it  is  perhaps  of  more  importance  than  in  gene 
ral  feeding,  that  the  provender  should  be  distributed  regularly ; 
plenty  of  soft  litter,  and  the  greatest  attention  to  cleanliness,  aid 
materially  in  fattening.  The  cow-house  ought  to  be  dark  and  quiet ; 
in  a  word,  all  the  conditions  ought  to  be  combined  which  conduce 
to  sleep,  and  secure  freedom  from  disturbance  of  every  description. 

The  age  at  which  cattle  fatten  most  readily  is  that  from  7  to  8 
years.*  Animals  under  this  age,  which  have  not  yet  come  to  their 
full  growth,  will  nevertheless  get  into  excellent  condition  ;  but  they 
require  both  longer  time  and  more  food,  for  the  reason,  apparently, 
that  they  are  still  forming  both  flesh  and  fat. 

In  fattening  during  winter,  which  is  done  almost  exclusively  with 
hay  in  some  countries,  an  ox  weighing  748  lbs.,  upon  40  lbs.  of  hay 
per  diem,  will  increase  by  about  2  lbs.  daily.     According  to  Mr. 

•  This  is  as  in  tlie  original,  and  may  be  true,  but  in  England  and  Scotland  we  hay* 
•eldom  an  opportunity  of  proving  it  so. — ^Eng.  Ed, 


454  THE    ox. — FATTENING. 

Low,  an  ox  weighing  770  lbs.,  and  consuming  about  2223  lbs.  of  tur- 
nips per  week,  if  he  thrive,  will  gain  in  the  same  space  of  time 
nearly  a  stone  in  weight.  Admitting  that  the  equivalent  number  for 
turnips  is  676, 1  find  that  the  ration  of  hay  for  this  allowance  comes 
out  47.8  lbs.,  having  produced  exactly  2  lbs.  of  increase. 

In  the  information  obtained  in  the  Ehenish  provinces  by  M.  Moll, 
in  regard  to  the  fattening  of  cattle  under  the  influence  of  a  regimen 
which  would  give  11  lbs.  of  hay  to  every  100  lbs.  of  dead  weight, 
the  animal  will  increase  one  third  in  weight  in  the  course  of  three 
or  four  months. 

To  these  general  results  I  add  a  few  particular  facts,  which  are, 
indeed,  the  only  data  in  rural  economy  that  can  ever  be  received  as 
having  much  value. 

In  a  series  of  experiments  which  he  undertook,  Mr.  Kobert 
Stephenson  proposed  to  compare  the  progress  of  the  increase  in 
weight  of  oxen  upon  different  alimentary  regimens.  Starting  with 
the  principle  which  we  have  already  established,  that  animals  con- 
sume a  quantity  of  food  in  proportion  to  their  weight  or  size,  when 
they  are  under  tiie  same  conditions,  he  had  of  course  to  divide  his 
stock  into  several  lots,  each  made  up  of  animals  of  as  nearly  as  pos- 
sible the  same  weight.  Oxen  of  two  years  old,  brought  up  on  the 
same  farm,  and  kept  in  the  same  manner,  were  the  subjects  of  exper- 
iment. I  shall  select  one  experiment,  in  which  the  observations 
were  made  upon  three  lots  of  six  beasts  each.  The  weight  of  each 
lot  was  ascertained  before  and  after  the  experiment,  which  was  car- 
ried on  for  119  days. 

The  first  lot  was  put  upon  white  turnips,  linseed  oil-cake,  beans, 
and  oats  ;  and  for  the  last  24  days  each  beast  had  20  lbs.  of  pota- 
toes every  day  in  addition. 

The  second  lot  was  fed  like  the  first,  with  the  difference  that  it 
had  no  cake,  and  that  during  the  last  24  days  the  quantity  of  pota- 
toes allowed  was  but  10  lbs.  per  diem. 

The  third  lot  had  no  other  provender  than  turnips. 

Here  are  the  weights  and  the  nature  of  the  provender  consumed 
by  the  animals  during  tlje  119  days,  with  a  column  added  contain- 
ing the  equivalent  in  hay  porresponding  with  each  of  the  articles 
consumed  : 

LOT  I.  LOT  II.  LOT  IIL 

,.,  .  1  EquWnlent  Equivalent  Equivalent  Equivalent 

Provender.  Weight  in  hay  Weight  in  hay  Weight  in  hay      assumed. 


in  lbs.  in  lbs. 


in  lbs. 


White  turnips..  1518           171.6  1628  184.8  1122  137 

Swedes. 1^336         1973.4           13884.8  1980  12012  1777.6     67« 

Beans 868         1559.8  858  1559  «'  "           23 

Oil-cake 889         1768  "  »  «  «           28 

Oats 173           279  178  279  "  "           63 

Potatoes 479           151  289.8  77  *♦  "         815 

Ration  expressed  in  hay    5904  8971  1905 

'^pUCr!^^"^^^f      49.7  848  16.0 

""JnVweiglJt^^^^"^:}       4.11  8.08  £.0 

It  therefore  plainly  appears  that  the  lot  which  had  the  largesf 


THE  OX. FATTENING.  455 

allowance  of  provender,  the  food  which  contained  the  greatest  quan- 
tity of  azotized  principles— of /esA,  in  fact — produced  the  largest 
amount  of  dead  weight  in  a  given  time,  and  that  the  lot  which  had 
the  shortest  allowance  increased  in  the  smallest  measure  both  in 
flesh  and  fat — results  which  might  have  been  readily  foreseen.  It 
is  also  apparent,  from  the  table,  that  in  proportion  to  the  nutritive 
value  of  the  article  consumed  by  each  lot,  the  increase  in  carcass 
weight  was  greatest  in  that  which  received  its  allowance  in  the  least 
bulk.  Thus  reducing  the  different  rations  to  a  standard  forage,  we 
find  that  in  the  first  lot,  which  was  most  plentifully  supplied,  100  of 
hay  gave  4.2  of  increased  weight ;  while  the  same  allowance  of  hay 
produced  6  in  the  third  lot  which  was  fed  parsimoniously.  This 
fact  is  most  readily  explained :  over  a  certain  limit,  the  more  food 
an  animal  receives,  the  smaller  is  the  fraction  which  \a  assimilated 
and  turned  to  use  in  the  body.  Breeders  have  consequently  discov- 
ered, that  it  is  by  no  means  generally  advantageous  to  push  animals 
beyond  a  certain  point  of  fatness.  The  excess  of  weight  which  is 
obtained  with  the  assistance  of  quantities  of  food,  exaggerated  as  it 
were,  no  longer  compensates  for  the  additional  expense  incurred. 
This  is  a  circumstance  which  Mr.  Stephenson's  experiments  also 
illustrate,  and  indeed  they  led  him  to  the  conclusion  which  has  just 
been  sta:ed.  Judging  by  the  market  price  of  the  several  articles  of 
provender  employed  by  this  distinguished  breeder  the  first  lot  appears 
to  be  that  the  fattening  of  which  turned  out  the  least  advantageously : 
while  each  pound  weight  of  flesh  produced  here  cost  about  5d.,  the 
price  of  production  in  the  second  lot  did  not  much  exceed  4d.  (45th  ;) 
in  the  third  it  was  a  little  more,  (4|ths.) 

With  these  observations  of  Mr.  Stephenson,  we  find  the  following 
numbers  to  express  the  daily  increase  in  weight  of  the  cattle  during 
the  period  of  fattening  : 

Average  weight  of  -      Hay  consumed  per  day  Inore«s«  per  head  Increase  per  day  and 

the  oxen  befor«                           and  per  biad.  in   119  days.                              par  hoad. 
fattening, 

lbs.                                               lbs.  lbs.                                          lb*. 

let  lot....  1115  49.7  247.6  2. 

2d  "  ....1016  84.8  281.6  1.9 

8d  "  ....  794  16.  112.6  0.9 

The  weight  of  the  several  animals  must  also  be  taken  into  account' 
in  seeking  to  estimate  the  increase  realized  upon  every  100  lbs.  of 
live  weight  during  the  fattening. 

In  the  1st  lot— 100  of  live  weight  in  119  days  gained,  22.2 
2d    "  "  22.8 

8d    «  "  14.2 

It  is  seldom  that  cattle  are  fattened  in  the  house  upon  clover  or 
lucern  in  the  green  state ;  nevertheless,  animals  will  fatten  upon 
this  forage  with  great  rapidity.  An  ox  will  eat  as  much  as  1  cwt. 
of  clover  cut  in  flower  in  the  course  of  the  day.  In  case  the  green 
food  should  relax  the  bowels  too  much,  a  fraction  of  the  allowance 
may  be  given  dried,  and  towards  the  end  of  the  fattening  a  little  cake 
may  be  given.  But  these  additions  do  not  appear  to  me  indispensa- 
ble ;  they  are  always  attended  with  additional  cost :  and  I  have 


456  THE  ox. FATTENING. 

frequently  seen  cows,  upon  green  clover  at  discretion,  acquire  a 
remarkable  degree  of  fatness,  although  they  had  not  ceased  to  be 
regularly  milked. 

In  those  countries,  the  nature  of  whose  climate  is    favorable  to 
pasturage,  the  rearing  of  cattle  presents  immense  advantages ;  but 
the  animals  can  only  be  fattened  in  those  that  are  the  most  fertile. 
The  meadow   that  sufiBces  for  the  growth  and  keep  of  a  bullock  will 
not  always  bring  the  animal  into  condition  for  the  butcher.     Those 
countries  where  the  climate  is  moist,  but  long  droughts  rarely  felt, 
where  neither  the  summer  heats  nor  the  winter  colds  are  excessive — 
the  conditions,  in  fact,  which  are  met  with  in  the  beautiful  pasture 
lands  of  England,  in  special — are  those  that  prove  most  favorable 
to  the  rearing  and  feeding  of  cattle.     The  pasture  lands  of  Nor- 
mandy and  Brittany  in  France,  of  Switzerland  and  Holland,  several 
of  the  provinces  watered  by  the  Khine,  &c.,  are  also  remarkable  for 
their  luxuriant  herbage.     In  such  situations  and  with  such  advatages, 
the  grand  object  with  the  farmer  is  the  production  and  fattening 
of  cattle.    Whenever  it  has  been  possible  to  lay  down  extensive  and 
productive  meadows,  it  is   now  beginning  to  be  clearly  understood 
that  the  introduction  of  even  the  best  system  of  rotation  were  to 
make  a  false  application  of  agricultural  science.     In  my  opinion,  there 
is  no  system  of  rotation,  however  well  conceived  and  carried  out. 
which  will  stand  comparison  in  point  of  productiveness  with  a  natu- 
ral meadow,  favorably  situated  and  properly  attended  to.     The  rea- 
son of  this  is  obvious,  and  follows  from  the  very  principles  which 
we  have  laid  down  in  treating  of  rotations.    The  whole  object  in  the 
best  system  of  husbandry  is  to  make  the  earth  produce  the  largest 
possible  quantity  of  organic  matter  in  a  given  time.     But  in  such  a 
system  we  are  limited  by  the  climate,  inasmuch  as  we  are  obliged  so 
to  arrange  matters  that  our  crops  shall  always  attain  to  complete 
maturity ;  the  consequence  of  which  is,  that  with  all  our  pains  the 
soil  remains  unproductive  during  a   certain  number  of  weeks  and 
mouths  towards  the  end  of  autumn,  in  the  early  spring,  and  through 
the  whole  of  the  winter.    But  upon  meadow  lands,  vegetation  is  in- 
cessant ;  the  winter  even  does  not  interrupt  it  completely  ;  it  still 
revives  and  makes  progress  on  the  bright  days  ;  and  in  the  spring" 
it  proceeds  when  the  mean  temperature  is  but  a  few  degrees  above 
the  freezing  point   of  water,  and  never   ceases  until  it  is  checked 
again  by  the  severer  cold  of  winter.    It  is  therefore  easy  to  obtain 
conviction  that  a  given  surface  of  meadow  land  must  necessarily 
produce  a  larger  quantity  of  forage  than  land  laid  out  in  any  other 
way.     It  is  true  that  the  forage  thus  obtained  will  not,  like  the  cereal 
grasses,  answer  immediately  for  the  support  of  man  ;  but  it  neverthe- 
less concurs  powerfully  in  this  by  producing  milk,  and  butter,  and 
cheese,  and  in  breeding  and  fattening  cattle ;  let  there  be  added  to 
all  these  the  advantages  of  what  may  be  called  a  permanent  vegeta- 
tion, that  the  cost  of  keeping  it  in  order  is  infinitely  less,  and  that 
there  is  no  risk  to  be  run  from  failures  of  crops,  and  the  vast  advan- 
tages of  meadow  or  pasture  land  will  meet  us  with  all  their  force. 


THE    OX. FATTENING.  457 

On  the  banks  of  the  Elbe,  in  Holland,  in  the  neighborhood  of 
Arnheira,  the  meadows  are  depastured  during  one  year,  and  cut, 
and  their  produce  made  into  hay  the  following  year,  and  so  on  alter- 
nately. The  cattle  are  fed  in  the  house  with  the  hay  during  the 
winter.  They  are  driven  out  into  the  pastures  in  May.  In  the  Low- 
Countries,  it  has  been  found  that  to  fatten  a  large  ox  a  surface  of 
meadow-land  of  about  9960  square  yards,  upon  which  he  will  pas- 
ture during  five  or  six  months,  was  necessary.  In  the  bottoms  of 
greatest  fertility  near  Dusseldorf,  it  has  been  calculated  that  to  keep 
a  cow,  an  extent  of  surface  equal  to  about  1800  square  yards  was  ne- 
cessary. 

In  countries  which  possess  rich  pasture  lands  oxen  are  put  to  fat- 
ten immediately  upon  the  richest  of  them.  In  the  valley  of  the 
Auge,  in  Normandy,  these  meadows  are  designated  as  herbages.  A 
meadow  of  this  kind  requires  a  rich,  damp  soil,  capable  of  retaining 
moisture.  It  is,  therefore,  to  a  considerable  extent  dependent  upon 
its  subsoil.  In  the  district  mentioned,  the  soil  of  the  pastures  con- 
sists of  a  thick  layer  of  vegetable  mould  resting  upon  clay ;  it  is 
therefore  very  rare  that  this  meadow  land  feels  the  effect  of  drought ; 
it  is  indeed,  only  in  the  early  spring  that  the  pasture  upon  such 
lands  sometimes  fails,  in  which  case  the  stock  must  of  course  be  as- 
sisted with  hay,  the  quantity  being  gradually  diminished  as  the  sea- 
son advances. 

M.  Dubois  finds  that  a  lean  ox  weighing  473  lbs.,  after  fattening 
in  the  valley  of  the  Auge,  will  weigh  763  lbs.,  so  that  he  will  have 
gained  290  lbs. ;  the  degree  of  fatness  attained  in  this  district  is  often 
prodigious.  M.  Dubois  mentions  oxen  which  weighr  d  when  fat  1760 
lbs.,  upwards  of  125  stone,  and  he  speaks  of  one  which  attained  the 
enormous  weight  of  2750  lbs.,  upwards  of  196  stone. 

The  height  of  the  oxen  fattened  in  the  herbages  of  the  Auge  va- 
nes from  4  ft.  7  in.  to  5  ft.  3  in.  measured  at  the  haunch ;  when 
thoroughly  fat,  the  four  quarters  will  weigh  from  550  lbs.  to  990  lbs., 
the  hide  will  weigh  from  70  lbs.  to  116  lbs.,  and  they  will  yield  from 
100  lbs.  to  150  lbs.  of  tallow. 

It  is  calculated  that  on  the  meadows  of  the  greatest  fertility,  a 
surface  of  2760  square  yards  are  required  to  fatten  a  large  ox  ;  on 
meadows  of  medium  fertility,  a  surface  of  4680  square  yards  are  re- 
quired to  fatten  an  ox  of  medium  size ;  on  those  of  the  third  quality, 
a  surface  of  3720  square  yards  is  deemed  necessary  to  fatten  a 
small  ox. 

M.  Dubois  calculates  the  quantity  of  green  fodder  consumed  by 
an  ox  during  the  eight  months  when  he  is  fattening,  is  equiva'ent  to 
6600  lbs.  in  dry  hay  ;  this,  at  least,  is  the  quantity  that  the  extent  of 
meadow  required  to  fatten  one  ox  would  produce.  The  average 
ration  of  green  forage  per  diem  is,  therefore,  equivalent  to  about  27 
lbs.  of  hay,  a  quantity  which  appears  small,  and  which  would  be  so 
in  effect,  were  not  the  oxen  kept  so  long  in  the  meadows.  M.Du- 
bois, indeed,  observes  that  in  the  stall,  with  a  ration  composed  of 
from  11  lbs.  to  13  lbs.  of  linseed  oil-cake  and  26  lbs.  of  hay,  an  ox 
will  become  sufficiently  fat  for  the  butcher  in  seventy  days,  and  will 
39 


458  THE    ox. — FATTENING. 

acquire  nearly  the  same  weight  that  he  would  have  gained  in  the 
course  of  seven  or  eight  months  in  the  meadows.  There  is  nothing 
surprising  in  this  fact,  inasmuch  as  the  ration  mentioned  by  M.  Du- 
bois, in  our  mode  of  viewing  it,  is  equivalent  in  nutritive  value  to  at 
least  81  lbs.  weight  of  hay;  the  quantity  of  oil-cake  alone  is  enough 
to  supply  a  good  pound  weight  of  fat  per  diem. 

In  old  Friesland,  where  the  pastures  are  excellent,  results  are  ob- 
tained which  may  be  compared  with  those  of  the  meadows  in  the 
valley  of  the  Auge  ;  an  ox  of  from  770  lbs.  to  990  lbs.  weight  will 
be  pushed  to  a  weight  of  from  1100  lbs.  to  1650  lbs.  on  a  surface 
of  meadow  land  between  3000  and  3600  square  yards  in  extent. 

In  the  meadows  of  the  Auge  the  fattening  goes  on  even  during  the 
winter ;  the  oxen  are  received  into  the  pastures  between  the  15th 
of  September  and  the  15th  of  November,  and  the  animals  pass  the 
winter  in  the  open  field  ;  but  they  receive  from  12  lbs.  to  26  lbs.  of 
hay  per  diem  until  the  month  of  April,  when  the  grass  has  already 
grown  sufficient  to  suffice  for  their  keep.  These  oxen  are  gener- 
ally fat  and  ready  for  market  in  July. 

In  these  observations  of  M.  Dubois,  the  fattening  has  reference  to 
the  neat  weight  of  the  carcass,  sinking  the  ofial,  as  it  is  said,  or  esti- 
mating the  weight  by  the  quarter.  The  most  esteemed  quarters  are 
the  hind  quarters,  which  are  found  to  weigh  rather  less  than  the  fore 
quarters,  although  the  difference  is  less,  the  higher  the  condition  of 
the  animal. 

It  is  long  since  various  means  have  been  devised  for  ascertaining 
the  neat  weight  of  a  living  animal,  or  in  other  words,  the  weight 
which  the  carcass  will  have  when  it  has  been  embowelled,  flayed, 
and  the  head  and  fat  cut  off.  These  various  parts  compose  what  ia 
called  the  offal.  It  is  readily  to  be  conceived  that  one  grand  feature 
in  the  excellence  of  an  ox  must  consist  in  the  great  relative  weight 
of  the  carcass  properly  so  called  in  comparison  with  the  offal ;  but 
it  may  easily  be  imagined  also  that  the  relations  in  the  weight  of 
these  two  different  portions  of  the  living  animal  will  vary  according 
to  the  state  of  fatness,  and  also  according  to  the  breed  and  the  age 
of  the  beast. 

Mr.  Andcrdon  has  found  that  an  ox  which  is  not  absolutely  lean 
will  give  for  every  100  lbs.  of  his  absolute  weight : 

Of  marketable  meat 58,6  lbs. 

An  ox  somewhat  fatter  will  yield 55      " 

And  one  completely  fat  as  many  as. .  .62.2  " 

Mr.  Layton  Coke's  estimate  is  : 

For  a  lean  ox 60  per  cent,  of  marketable  m«»t 

For  an  ox  In  middling  condition. . .  65  " 

And  for  a  fat  ox 78  " 

These  estimates  appear  to  me  exaggerated,  and  I  much  doubt  from 
the  sales  of  cattle  which  we  make  ourselves,  whether  they  would 
readily  be  admitted  by  the  buyers  ;  they  are  in  fact  too  high  as  re- 
gards the  available  meat. 

From  a  great  number  of  actual  trials  made  with  animals  of  about 
two  years  old,  and  which  were  all  as  nearly  as  poseble  in  the  same 


THE    OX. FATTENING.  469 

condition,  Mr.  Stephenson  was  enabled  to  determine  with  great  ac- 
curacy the  actual  weight  of  the  butcher's  meat  in  contrast  with  the 
entire  weight  of  the  animal.  Mr.  Stephenson  comes  to  the  folio  ysr- 
ing  conclusions  : 

Butcher's  meat  per  cent 57  7 

Tallow :. :.: 80 

The  hide ;;;;.'  sis 

The  entrails  and  offal 28.8 

100.0 

The  precise  quantities  of  marketable  meat  and  of  offal  have  also 
been  determined  by  Mr.  Mallo  in  an  ox  of  the  Durham  breed  which 
was  slaughtered  in  his  presence.  The  weight  of  the  animal  on  its 
feet  was  1496  lbs. 

Per  cenfage  of 
m.       .  «  ,  ...  ""•  ""« weight. 

The  two  fore  quarters  weigned 406.9  )  r^  ,• 

The  two  hind             "              428.5  f  °^'* 

Theskin 62.7  4,2 

Thetadow 112.0  7.5 

The  blood 110,0  7,4 

The  head,  fat,  and  entrails 881,7  26.5 

1496.0      100.0 

These  relations  as  to  meat,  tallow,  and  skin  agree  in  a  very  con- 
siderable measure  with  the  estimates  of  Mr.  Stephenson. 

Sir  John  Sinclair  gives  the  following  numbers  as  the  results  ob- 
tained in  connection  with  an  ox  of  the  Devonshire  breed,  slaughtered 
at  the  age  of  3  years  and  10  months. 

Weight  of  the  living  animal,  1549,6  lbs, 

P»r  centageof 
lbs.  the  live  weight. 

Butcher's  meat,  tho  four  quarters 1083.5  70,0 

Theskin 84.9  5,5 

Tallow 143.2  9,2 

Entrails  and  blood 163.6  10.5 

Head  and  tongue 86.7  2.4 

Feet 17.1  1.4 

Heart,  liver  and  lungs 20.4  1.8 

1549.4         100,0 

The  animal  here  was  not  in  prime  condition.  On  the  whole,  the 
relations  as  stated  by  Mr.  Stephenson  may  be  taken  as  those  that 
will  be  found  nearest  the  average  truth,  and  as  his  numbers  are  de- 
duced from  numerous  actual  experiments,  I  feel  disposed  to  adopt 
them.  M.  Dubois  has  found  that  an  ox  which  will  weigh  473  lbs., 
sinking  the  oftal,  will  be  brought  by  fattening  to  the  weight  of  763 
lbs.     We  have,  therefore,  for  the  weight  of  an  animal  as  it  stands  : 

Before  fattening 828  lbs. 

After  fattening 1386 

Gain  in  weight 508 

The  fattening  having  been  effected  in  eight  months,  the  absolute 
increase  in  weight  per  diem  will  amount  to  2  lbs.;  the  increase  per 
cent,  upon  the  weight  is  61.4. 

We  have  seen  that  during  the  fattening,  the  mean  consumption, 
reckoning  the  provender  in  hay,  amounts  to  6600  lbs.:  the  increase 
obtained  being  508  lbs.  gives  16.9  lbs.  of  living  solid  for  every  220 


^^0  THE    HORSS. 

lbs.  of  hay  consnmcd.  Lastly,  the  mean  ration  being  settled  by  M. 
Dubois  at  26.4  lbs.  of  hay  per  head  and  per  diem,  and  the  weig-ht  of 
tb3  animal  on  being  taken  into  the  meadow  being  828.3  lbs.,  this  ra- 
tion corresponds  to  7.1  lbs.  of  hay  for  everj  220  ibs.  weight  of  the 
living  animal. 

To  sura  up  from  the  facts  just  stated  on  the  subject  of  fattening,  it 
appears  that  the  increase  per  day  is  : 

According  to  Thayer 0.98  per  cent  on  the  hay  consumed. 

"  Low 0.91 

"  Stephenson,  Ist  lot 0.94  " 

2d        20.99  " 

3d        0.45  " 

Dubois 0.95  •* 

^  IV.      OF   HORSES. 

In  what  follows  I  shall  limit  myself  to  the  consideration  of  the 
horse  in  his  relation  to  agricultural  industry,  and  shall  give  the  re- 
sult of  certain  experiments  which  I  have  made  upon  his  growth  with 
a  view  of  solving  the  question,  much  disputed  in  various  places  at 
the  present  time,  whether  or  not  the  general  farmer  can  breed  hoi-ses 
witli  advantage  to  himself. 

The  horse  employed  in  farm  labor  ought  to  be  spirited  and  strong  : 
attention  to  external  form  is  only  to  be  given  in  so  far  as  it  is  an 
indication  of  the  qualities  that  are  required.  He  ought  therefore  to 
be  broad  in  the  chest  and  in  the  haunches,  and  his  muscular  system 
ralist  in  general  be  decidedly  developed.  A  horse  of  considerable 
size,  if  he  be  otherwise  exempt  from  defects,  is  generally  preferable 
to  a  small  animal ;  he  is  stronger,  takes  longer  steps,  and  does  more 
for  his  keep  than  the  other.  We  are  not  to  require  in  the  draught- 
horse  the  vivacity  and  amount  of  spirit  which  we  look  for  in  the 
saddle  horse,  yet  he  ought  to  have  that  liveliness  which  is  almost 
always  a  sign  of  health  in  animals. 

Thaer  does  not  approve  of  the  practice  commonly  followed  at  this 
time  of  mixing  with  good  draught  horses  the  blood  of  stallions  of 
elegant  shape,  but  little  adapted  to  stand  hard  work.  Although  this 
remark,  is  not  without  truth,  it  is  still  impossible  to  deny  that  in  many 
cases  the  employment  of  stallions  of  some  breeding  has  much  im- 
proved the  race  of  draught-horses  in  various  districts.  It  is  not 
besides  unworthy  of  attention,  that  it  is  really  important  for  the 
farmer  to  have  a  breed  which  he  can  readily  dispose  of  to  advantage, 
particularly  in  those  countries  where  horses  for  cavalry  and  artillery 
service  are  in  request.  My  own  observation  would  lead  me  to  say, 
that  the  breeds  in  France  are  frequently  improve*^  by  crossing  with 
stallions  of  the  royal  studs.  The  effect  from  this  procedure  has  not 
]ierhaps  been  so  great  as  might  reasonably  have  been  expected,  still 
evident  progress  has  been  made. 

The  mare  will  take  the  stallion  at  about  the  age  of  three  years  ;  but 
it  is  seldom  that  the  animal  is  covered  at  so  early  an  age  ;  on  the 
farm  she  will  be  at  least  five  or  six  years  of  age  before  this  is  allow- 
ed, especially  if  the  animal  is  to  be  worked  during  the  time  she  is 
with  foal  J  and  the  same  consideration  leads  us  to  say,  that  a  mare 


THE    HORSE.  461 

ought  not  to  be  covered  oftener  than  once  in  two  years,  although  it 
is  very  possible  to  have  a  foal  from  her  every  year,  for  she  frequent- 
ly comes  into  season  towards  the  11th  day  after  foaling,  and  she 
goes  with  young  for  a  term  which  varies  between  333  and  346  days. 

A  brood  mare  may  be  employed  in  ordinary  work  during  the  first 
period  of  her  pregnancy ;  but  when  the  time  is  further  advanced, 
when  she  is  in  the  tenth  month,  for  example,  every  possible  precau- 
tion must  be  taken  against  accident.  This  is  the  period  at  which 
we  withdraw  our  brood  mares  from  the  common  stable,  and  put  them 
into  separate  boxes.  After  she  has  foaled,  the  mare  receives  in 
small  quantities  and  frequently  repeated,  warm  drinks  and  bran 
mashes.  While  she  is  giving  suck,  her  food  ought  to  be  of  a  more 
substantial  or  better  kind  than  that  which  is  generally  allowed. 

The  mare  may  be  put  to  light  work  twenty  days  after  she  has 
foaled ;  but  it  is  requisite  not  to  demand  any  thing  like  exertion  from 
her  within  eight  or  ten  weeks  after  this  event ;  she  then  goes  out 
accompanied  by  her  foal  which  is  generally  suckled  for  about  one 
hundred  days.  Foals  are  frequently  brought  up  in  the  stable  or  in 
the  loose  box  ;  this  is  our  practice  in  Alsace  ;  but  it  is  well,  with  a 
view  to  the  growth  and  health  of  the  young  animal,  that  it  be  taken 
out  every  day.  On  quitting  the  teat,  foals  are  fed  upon  choice  hay  ; 
ill  the  course  of  the  second  year  a  portion  of  the  hay  should  be  re- 
placed by  an  allowance  of  oats,  and  in  the  season  the  use  of  green 
clover  cannot  be  too  highly  recommended. 

According  to  Thaer,  the  daily  allowance  to  a  horse  of  middling 
height,  and  doing  ordinary  work,  may  be  regarded  as  good  when  it 
consists  of: 

Hay 8.2  lb9.  —Hay. 8.»  lbs. 

Oats  9.2        —Ditto 14.2 

Allowance  reckoned  in  hay. 22.4 

In  England  the  following  allowance  has  been  particularly  men- 
tiond  as  that  of  certain  well  conducted  stables. 

Cut  Hay 11.0  Iba.  -=  Hay 11.0  lbs. 

Cutstraw 2.2         —Ditto 0.65 

Oats 11.0        —Ditto 16.9 

Beans 1.1        —Ditto 4.T 

Allowance  reckoned  In  hay. 8?  .2 

According  to  M.  Tassey,  veterinary  surgeon  in  the  Municipal 

Guard  of  Paris,  the  provender  of  the  horses  in  this  corps  in  1840 

consisted  of : 

Hay nibs.  —Hay 11  lbs. 

Oats.  8        —Ditto ,...., 12 

Straw  for  litter 11        -Ditto 2i 

Total  allowance 25^ 

The  same  authority  reckons  that  horses  employed  in  severs 
draught  receive  or  require  : 

Hay 16>lb8.-Hay  16*lb» 

Oata.  IT         —Ditto 26 

Total  allowsn/vo  . .    42# 

39* 


462  THE    HORSE. 

Until  very  lately  (previoDsly  to  1840)  the  allowance  of  troop 
horses  in  the  French  army  consisted  for  the  reserve  cavalry  of : 

Hay nibs.  —Hay 11  lbs. 

Oats  8         =- Ditto 12 

Straw. 11         =-Ditto 2^ 

Total  allowance 26* 

For  the  cavalry  of  the  line  : 

Hay 8.8  lbs. -=  Hay 8.8  lbs. 

Oats 7.6         =- Ditto 11.5 

Straw 11  =Ditto 2.T 

Total  allowance 28.0 

For  the  light  cavalry : 

Hay 8.81b8.-=Hay 8.8  lbs. 

OatB 6.6         —  Ditto 10.1 

Straw 11  =Ditto 2.7 

Total  allowance.  21'6 

Influenced  by  the  consideration  of  the  frequent  indifferent  quality 
of  hay,  and  its  injurious  effect  upon  the  health  of  the  horse,  it  was 
decided  in  1841  to  replace  a  portion  of  the  hay  ration  by  a  larger 
quantity  of  oats,  an  article  much  less  liable  to  be  adulterated,  or  to 
be  indifferent  in  quality.  The  allowance  now  consisted  for  the  re- 
serve cavalry  of: 

lbs.  lbs. 

Hay 1.8  ="  Hay 8.8 

Oats. 9.2=  Ditto 14.2 

Straw 11     =Ditto 2.7 

Total  allowance 25.7 

For  the  cavalry  of  the  line  : 

lbs.  lbs. 

Hay 6.6  —Hay 6.6 

Oats  8.8— Ditto 18.5 

Straw 11     —Ditto 2.7 


Total  allowance 22.8 

For  the  light  cavalry  : 

lbs.  lbs. 

Hay 6.6— Hay , 6.« 

Oats 8.8— Ditto 12.8 

Straw 11     —Ditto 2.7 

Total  allowance 22.1 

From  what  precedes,  it  appears  that  the  substitution  of  oats  for 
hay  was  made  upon  a  calculation  which  squares  well  with  the  theo- 
retical inferences  in  regard  to  the  relative  nutritive  powers  of  these 
two  articles. 

The  allowance  to  the  horse  ought  to  be  distributed  into  three  por- 
tions, constituting  as  many  meals,  and  put  before  him  in  the  morning 
before  going  to  work,  in  the  middle  of  the  day,  and  in  the  evening  ; 
he  is  generally  watered  at  meal  times.  It  is  also  highly  advantage- 
ous to  the  health  of  the  horse  that  he  be  made  to  work  with  a  cer- 
tain regularity.  Our  horses  at  Bechelbronn,  upon  an  allowance 
equivalent  to  33  lbs.  of  hay,  work  from  8  to  10  hours  a  day,  having 
an  hour's  rest  at  midday. 


THE    nORSE. 


4t)3 


There  is,  of  course,  a  certain  relation  between  the  height  or,  if 
you  will,  the  weight  of  the  horse,  and  the  quantity  of  provender  he 
requires.  Some  attention,  as  we  have  seen,  has  been  given  to  this 
point,  in  connection  with  horned  cattle  ;  but  with  reference  to  the 
horse  I  know  of  no  data  but  such  as  I  myself  possess.  Seventeen 
horses  and  mares,  aged  from  5  to  12  years,  and  having  each  proven- 
der equivalent  to  33  lbs.  of  meadow  hay,  weighed  together  18,190 
lbs.  The  mean  weight  of  each  horse  being  represented  by  the  num- 
ber 1070  lbs.,  we  perceive  that  for  every  100  lbs.  of  live  weight  6.7 
lbs.  of  meadow-hay  are  required  for  the  daily  ration,  the  horses 
working  from  8  to  10  hours  a  day.  This  relation  differs  very  little 
from  that  which  we  have  obtained  in  reference  to  cattle. 

I  was  anxious  to  ascertain  the  rate  of  growth  of  the  horse ;  and 
in  connection  with  our  breed,  which  have  a  mean  weight  of  about 
1100  lbs.,  I  found  that  the  foals  weighed  as  follows  : 


d 

a 

a 

^ 

S 

H 

1 

a 

,0 

bo 

Vi-O 

\fA 

|| 

Names. 

^ 
"S 

■s 

^ 

^ 
a 

11 

•s=s 

fl 

o 

2  E3 

S+*      s  s 

1 

I 

§ 
^ 

Increa 
during 

Increa 
P 

1                     1    lbs. 

lh8. 

T 

lbs.      lbs. 

Filly  of  Chevreuil    25  May,  1842 1    110 

20  Aug.  1842 

294.8 

184.8      2.1 

Filly  of  Hechler       12  June,  1842:    113 

7  Sept.  1842 

286. 

87 

172.        1.9 

Filly  of  Brunette.     12  June,  1842:    113 

7  Sept.  1842 

854. 

87 

241. 

2.7 

The  mean  increase  per  day  during  the  period  of  suckling  in  thtj 
three  cases  quoted  above,  therefore,  appears  to  have  been  rather 
more  than  2  and  /oths  lbs.  avoirdupois. 

Immediately  after  weaning,  young  horses  appear  to  experience  an 
arrest  of  their  growth  for  some  short  time,  an  event  which  indeed 
happens  to  animals  generally.  I  found,  for  example  that  Chevreuil's 
filly,  which  on  the  day  of  weaning  weighed  294  lbs.,  nine  days  after- 
wards weighed  but  288  lbs.,  and  had  consequently  lost  6  lbs. 

I  shall  add  a  few  weighings  of  horses  further  advanced  in  age, 
although  still  young  : 

Alexander,  a  colt,  weighed  at  birth  110  lbs. :  at  the  age  of  128 
days,  337  lbs. ;  increase  227  lbs.,  or  about  1.8  per  diem  :  51  days 
afterwards,  490  lbs. ;  increase  105  lbs.,  or  per  day  1.4  lb. 

Finette,  a  filly,  weighed,  when  weaned  at  the  age  of  86  days,  295 
lbs. ;  83  days  afterwards,  396  lbs.  :  increase  101  lbs.  ;  per  day,  1.1 
lb. 

Hechler's  filly  weighed  when  weaned  at  the  age  of  87  days,  286 
lbs. ;  65  days  afterwards,  358  lbs. ;  increase  72  lbs.  or  per  day  1 J 
lb. 

From  what  precedes  we  may  conclude  : 


*38 


464  THE    HOG. 

1st.  That  foals,  the  issue  of  mares  weighing  from  960  to  1100  lbs., 
weigh  at  birth  about  112  lbs. 

2d.  That  during  suckling  for  three  months,  the  weight  increases 
in  the  relation  of  278  to  100,  and  that  the  increase  corresponds  very 
nearly  to  2  and  j\  lbs.  avoirdupois  for  each  individual  per  diem. 

3d.  That  the  increase  of  weight  per  diem  of  foals  from  the  end 
of  the  first  to  the  end  of  the  second  year,  is  about  1  j\  lbs.  avoirdu- 
pois ;  and  that  towards  the  third  year,  the  increase  per  day  falls 
something  under  1  lb.  avoirdupois.  After  three  years  complete,  the 
period  at  which  the  horse  has  very  nearly  attained  his  growth  and 
development,  any  increase  becomes  less  and  less  perceptible.  These 
conclusions  in  regard  to  the  horse,  differ  very  little  from  those 
which  I  have  had  occasion  to  draw  in  connection  with  horned  cattle. 

I  have  also  made  a  few  experiments  with  reference  to  the  quantity 
of  provender  consumed  by  foals  in  full  growth,  and  have  found  that 
Alexander,  Finette,  and  Hechler's  filly,  weighing  together  1106 
lbs.,  consume  per  day  : 

Hay 19.8— Hay 19.8 

Oats T    =Ditto....; 11 

Total  allowance 80.8 


Per  head 10.22 

The  mean  weight  of  these  foals  was  368.6  lbs.,  so  that  the  hay 
consumed  for  every  hundred  pounds  of  live  weight  was  2.85  lbs., 
with  which  allowance  the  daily  increase  amounted  to  about  1.2  lb. 
Consequently,  a  mixed  provender,  equivalent  to  100  lbs.  of  hay,  had 
produced  12  lbs.  of  live  weight.  I  must  confess  that  this  result 
appears  to  be  somewhat  too  favorable,  but  I  can  only  set  down  the 
numbers  as  they  presented  themselves  to  me. 

The  flesh  of  the  horse  is  not  generally  used,  or  at  least  openly 
used,  as  food  for  man,  though  there  are  countries  in  which  it  is  ex- 
posed for  sale  and  commonly  eaten.  At  Paris,  indeed,  in  times  of 
scarcity,  horse-flesh  has  been  consumed  in  quantity.  During  the 
Revolution,  a  knacker  exposed  publicly  for  sale,  in  the  Place  de 
Greve,  joints  from  the  horses  which  he  had  killed,  and  the  sale  con- 
tinued for  three  years  without  any  ill  efi*ect  ;  in  1811,  a  scarcity 
obliged  the  Parisians  to  have  recourse  to  the  same  kind  of  food,  and 
it  is  said,  indeed,  that  the  traffic  in  horse-flesh  as  an  article  of  human 
sustenance  is  still  continued  to  a  very  considerable  extent  in  the 
French  metropolis  ;  at  the  present  moment,  a  distinguished  writer  on 
Medical  Police,  M.  Parent-Duchatelet,  has  even  proposed  to  legalize 
the  sale  of  horse-flesh  as  food  for  man. 


There  is  perhaps  no  farming  establishment  which  does  not  keep 
a  certain  number  of  hogs,  a  measure  by  which  ofial  of  all  kinds  that 
would  jjo  directly  to  the  dunghill,  is  turned  to  the  very  best  account. 
The  dairy,  the  kitchen-garden,  and  the  kitchen,  all  yield  their  con- 
tingent of  food  to  the  pig-stye,  which  is  moreover  an  excellent 
nuians  of  using  up  certain  portions  of  the  harvest    But  the  rearing 


THE    HOG.  465 

and  fattening  of  hogs,  although  frequently  looked  upon  as  mattrra 
of  course,  and  requiring  very  little  care,  do  in  fact  demand  consider- 
able attention  and  certain  conveniences  in  situation.  The  rearing 
of  hogs,  in  a  general  way,  may  be  said  to  suit  the  small  farmer 
better  than  the  great  agriculturist. 

Our  common  domestic  hog  appears  to  derive  his  origin  from  the 
common  wild  hog  of  Europe.  The  breeds  are  extremely  numerous. 
The  black  hog,  covered  with  rather  fine  hair,  and  commonly  found 
in  Spain,  is  a  native  of  Africa.  This  is  the  race  which  has  been 
carried  to  South  America,  where  it  has  multiplied  in  a  truly  surpris- 
ing manner.  It  grows  rapidly ;  and  if  it  has  little  to  recommend 
it  with  reference  to  fattening,  it  is  nowise  nice  in  the  matter  of  food 
and  general  entertainment ;  the  flesh  is  excellent  when  the  animal 
has  been  kept  upon  the  banana,  and  fattened  off  upon  Indian  corn. 

The  hogs  of  the  east  of  Europe  are  remarkable  for  their  size ; 
they  are  of  a  deep  gray  color,  and  have  very  long  ears ;  they  are 
not  very  prolific,  the  brood  swine  having  rarely  more  than  four  or 
five  at  a  birth.  The  Westphalian  breed,  on  the  contrary,  though 
they  resemble  the  last;  are  highly  prolific,  the  litter  generally  con- 
sisting of  from  ten  to  twelve.  In  Bavaria  the  hogs  are  remarkable 
for  the  smallness  of  their  bones,  and  the  readiness  with  which  they 
take  on  fat.  Lastly,  the  Chinese  race,  which  is  common  in  England, 
and  begins  to  extend  on  the  continent,  differs  from  those  hitherto 
known,  in  having  the  back  straight  or  even  hollow,  and  the  belly 
large.  This  breed  is  also  remarkable  for  its  quietness ;  the  pork 
which  it  yields  is  of  the  very  best  quality. 

One  of  the  great  advantages  connected  with  the  hog  being  its 
extreme  fecundity,  it  is  important  to  have  a  breed  which  is  distin- 
guished in  this  respect.  There  are  some  brood  swine  which  have 
regularly  borne  ten  or  fifteen,  and  even  eighteen  pigs  at  a  litter  ;  a 
more  general  number  is  eight  or  nine. 

According  to  Thaer,  the  hog  that  is  disposed  to  take  on  fat  is 
distinguished  by  length  of  body,  long  ears  and  a  pendulous  belly. 
The  hog  attains  his  growth,  at  the  end  of  about  a  year,  until  which 
time  the  female  ought  not  to  be  put  to  the  boar.  One  boar  generally 
suffices  for  about  ten  females. 

The  hog, 'as  all  the  world  knows,  is  an  animal  the  least  dainty  in 
his  food ;  he  is  omnivorous,  nothing  comes  amiss  to  him  ;  but  his 
food  is  by  no  means  matter  of  indifference  when  the  quality  of  the 
flesh  comes  to  be  considered.  Thaer  seems  to  think  that  maize  is 
of  all  articles  that  which  is  the  best  for  feeding  swine  ;  and  I  have 
had  occasion  to  verify  the  accuracy  of  his  conclusion  in  South 
America,  where  I  may  add  it  is  found  that  the  oily  fruit  of  the  palm- 
tree  contributes  powerfully  to  the  fattening. 

Husbandry,  in  regard  to  the  hog,  comprises  two  distinct  periods : 
the  growth  of  the  animal,  and  his  fattenmg.  It  is  generally  admit- 
ted that  it  is  most  advantageous  not  to  fatten  swine  for  the  butcher 
until  they  have  completed  or  nearly  completed  their  growth.  A 
hog  which  has  been  well  kept  from  the  period  of  its  birth,  may  be 
put  up  to  fatten  at  the  age  of  about  a  year.    The  female  shows  signs 


466  THE    HOG. 

of  heat  at  the  age  of  about  five  or  six:  months,  and  goes  with  young 
on  an  average  115  days,  and  will  produce  regularly  two  litters  per 
annum  ;  when  particularly  well  kept,  she  may  have  three  litters  in 
the  course  of  from  thirteen  to  fourteen  months. 

The  hogs  which  are  destined  to  be  fattened  for  the  knife  are  ge- 
nerally cut  at  the  age  of  six  weeks,  particularly  if  they  are  to  be 
put  up  to  fatten  at  the  age  of  nine  or  ten  months,  as  is  often  done. 
Almost  all  the  varieties  of  roots  and  grain  produced  upon  the  farm 
are  suitable  for  the  maintenance  of  the  hog  ;  but  in  Alsace,  and  I 
believe  generally,  the  staple  is  the  steamed  potato,  with  which  are 
associated  various  articles  in  smaller  quantity,  such  as  peas,  aod 
barley  and  rye  meal,  &c. 

The  farrow  sow  ought  to  have  food  by  so  much  the  more  abun- 
dant and  nutritious  as  she  is  required  to  suckle  a  larger  number  of 
pigs.  Our  allowance  at  Bechelbronn  to  the  hog  with  five  young 
ones  during  the  six  weeks  of  suckling  is  as  follows : 

lbs.  lbs. 

Steamed  potatoes 24.75  «=  hay 7.8 

Evemeal 2.46=-    "  40 

Skim  milk 13.2=-   "  6.2 

Total  allowance  18.0 

After  the  fifth  week,  when  the  animal  is  no  longer  giving  suck, 
tlie  ration  consists  of: 

lbs.  lbs. 

Steamed  potatoes 12.1  — =  hay 7-8 

llye  tnea!        1.0—    "  1.6 

Skim  milk  [sour] 6.5—   " 8.8 

Total  Allowance 12.2 

This  allowance  is  gradually  reduced  to  the  end  of  the  second 
mouth  after  the  farrowing,  when  the  animal  is  upon  the  maintenance 
ration  of  the  farm,  consisting  of : 

lbs.                                               lbs. 
Steamed  potatoes 16.5—  hay 5.2 

The  potatoes  are  mixed  with  dish  washings,  which  certainly  con- 
tribute to  improve  their  nutritive  power,  although  I  am  altogether  at 
a  loss  to  estimate  the  value  of  the  article. 

The  young  pigs  begin  to  taste  the  food  given  to  the  mother  at  the 
age  of  about  a  fortnight,  but  they  never  take  to  this  kind  of  food 
freely  until  they  are  four  or  five  weeks  old  and  are  weaned  ;  up  to 
this  time  they  have  an  allowance  of  skim  milk  and  whey.  To  five 
pigs  at  the  time  of  weaning  we  allowed  per  day : 

lbs. 

steamed  potatoes 22.0-=  bay 7.8  per  head  1.4 

Eyemeal 1.0—"  1.6        "       0.88 

Sklmmilk 6.0—    "  2.8        "       0.67 

29.6  "llJ 

This  allowance  was  modified  by  degrees  ;  the  quantities  of  milk 
and  rye  meal  were  gradually  abridged,  and  the  proportion  of  pota- 
toes increased,  so  that  about  the  third  month  the  allowance  per  head 
was  from  11  to  13  lbs.  of  potatoes  mixed  with  greasy  water.    This 


THE    HOG.  467 

is  the  reg-imen,  equivalent  to  about  5  lbs.  of  hay,  upon  which  our 
store  pigs  are  maintained  until  they  ate  put  up  to  fatten.  During 
tiie  three  months  which  follow  the  weaning,  therefore,  we  may 
reckon  that  each  animal  has  consumed  3.8  lbs.  of  meadow-hay  per 
day,  and  that  from  the  third  month  the  consumption  may  be  repre- 
sented by  5.2  lbs.  of  the  same  article. 

We  have  attempted  in  vain  to  replace  the  potato  by  rape  or  madia 
oil-cake  ;  the  pigs  refused  it  obstinately  ;  but  they  showed  no  objec- 
tion to  poppy  seed,  walnut  and  linseed  eake ;  during  the  season  they 
will  also  eat  clover,  and  are  partly  maintained-  upon  this  plant.  In 
summer  they  are  put  entirely  upon  green  meat,  animals  from  five  to 
six  months  old  consuming  about  19  lbs.  of  clover  a  day,  a  quantity 
which  represents  very  nearly  5  lbs.  of  clover  hay. 

The  hog  may  be  fattened  at  any  age  ;  but  as  we  have  already  said, 
it  is  not  generally  advisable  to  fatten  before  he  is  ten  months  or  a 
year,  some  say  fifteen  months  or  a  year  and  a  half  old,  at  which 
period  the  animal  is  undoubtedly  in  flesh  and  at  its  full  growth.  The 
other  extreme  limit  appears  to  be  about  five  years  ;  but  it  is  only  a 
brood  sow  that  is  ever  kept  to  five  years  of  age.  It  is  generally 
allowed  that  twelve  weeks  are  required  to  bring  a  hog  into  prime  con- 
dition, when  he  ought  to  have  a  layer  of  fat  under  the  skin  upwards 
of  an  inch  in  thickness.  Sixteen  weeks  may  be  required  to  obtain 
an  animal  really  fat ;  and  twenty  weeks  to  have  him  at  the  highest 
point  that  is  attainable.  The  hog  requires  to  be  fed  regularly. 
After  weaning,  pigs  should  have  five  or  six  meals  in  the  course  of 
the  day ;  the  number  of  meals  is  diminished  gradually,  and  towards 
the  end  of  two  months  they  amount  to  but  three  in  all. 

I  was  curious  to  ascertain  the  weight  of  the  pigs  at  the  moment  of 
their  birth,  so  as  to  determine  their  rate  of  increase  during  the  period 
of  suckling.    On  the  5th  of  September  a  sow  farrowed  a  litter  of 

five. 

lbs 
No.  1  weighed....  2.205 
No.  2  "  ....8.025 
No.  8  "  ....2.476 
No.  4  "  ....2.750 
No.  5       "       ....8.800 

Weight  of  the  litter 13.756 

Average  weight  per  head 2.761 

On  the  11th  of  October  the  weight  of  the  litter  was  86.6  lbs.,  or 
17.3  lbs.  per  head  ;  increase  in  thirty-six  days,  73.2  lbs.  ;  per  head, 
14.6  lbs. :  per  day,  0.409  lbs.  On  the  15th  of  November  the  weight 
was  177  lbs.  :  increase  in  thirty-five  days,  90.2  lbs. :  per  head,  18 
lbs. ;  per  day,  0.506.  During  the  thirty-six  days  of  suckling,  con- 
sequently, 100  of  live  weight  at  birth  had  become  632. 

In  another  instance,  I  found  that  eight  pigs  which  at  the  time  of 
weaning  weighed  114  lbs.  or  14.3  lbs.  per  head,  at  a  year  old 
weighed  1320  lbs.,  or  165  lbs.  per  head :  increase  in  eleven  months 
1206  lbs.,  or  150  lbs.  per  head. 

The  increase  per  diem  since  the  weaning  had  been  0.4. — not  quite 


468  THE   noG. 

half  a  pound ;  and  as  the  food  consumed  may  be  represented  by  5.2 
lbs.  of  hay  per  day  and  per  head,  it  will  follow  that  100  of  forage 
had  produced  8.58  of  live  weight.  This  ratio  is  too  high,  however  : 
for  these  pigs  besides  the  regular  allowance  had  whey  and  various 
scraps  of  which  no  account  was  kept ;  and  we  know  that  whey 
alone  contains  a  considerable  quantity  of  the  representatives  both 
of  flesh  and  fat. 

Baxter  came  to  some  interesting  conclusions  on  the  growth  and 
fattening  of  young  hogs.  Four  animals  each  of  the  age  of  nine 
months  weighed  at  the  beginning  of  the  experiment  458.2  lbs.  ; 
twenty-one  days  afterwards,  620.8  lbs. :  increase  of  weight  162.6 
lbs.,  to  obtain  which  there  were  consumed  : 

lbs.  lbs. 

Barley 151  equivalent  to  hay,  250 

Beans 140.8  "                      611 

Maltgrains 440  «                     26T 

1229 

So  that  a  quantity  of  nutritive  matter  represented  by  100  lbs.  of 
hay  produced  13.21  lbs.  of  live  weight. 

Assuming  the  weight  of  each  pig  of  nine  months  old  before  her 
fatting  to  have  been  29  lbs.,  the  increase  per  head  was  40.6  lbs.  in 
the  course  of  twenty-one  days,  or  at  the  rate  of  1.9  lbs.  each.  Bax- 
ter reckoned  the  carcass  weight,  sinking  ofiFal,  at  7.4  per  cent. 

One  of  the  pigs  between  nine  and  ten  months  old  weighing  159.5 
lbs.,  at  the  end  of  twenty  days  weighed  198.8  lbs. :  increase  in 
twenty  days,  39.3  lbs. ;  increase  per  day,  1.9  lbs.  During  these 
twenty  days,  the  animal  had  consumed  188  lbs.  of  barley,  equivalent 
to  314  lbs.  of  hay.  The  increase  would  consequently  give  for  every 
100  lbs.  of  hay  consumed  an  increase  of  live  weight  of  12.52,  say 
12^  lbs. 

Arthur  Young,  by  keeping  pigs  of  a  year  old  on  peas-meal,  obtain- 
ed the  following  results. 

No.  1  weighed  99.0 :  85  days  afterwards,  167.5 :  gain  58 J5 :  per  day  l.fr2 
No.  2       "       91.7;  42  "  145.4;  68.7;        "       1.876 

No.  8        "        86.6;  63  "  189.4;  62.8;        •'       0.886 

I  shall  here  give  two  series  of  observations  made  at  Bechelbronn 
on  the  fattening  of  hogs.  September  6th,  1841,  seven  hogs,  aged 
fifteen  months  each,  already  in  good  condition,  were  put  up  to  fatten. 
They  had  hitherto  had  the  usual  hog's  food — sour  milk  and  boiled 
potatoes  after  weaning  ,  by  and  by  from  11  to  15  lbs.  of  potatoes, 
whey,  and  dish  washings.  The  seven  porkers  weighed  1691.8  lbs. ; 
or  241.67  lbs.  each.  The  increase  had  been  at  the  rate  of  0.528, 
rather  better  than  half  a  pound  per  day  and  per  head,  supposing  them 
to  have  weighed  13.7  lbs.  each,  at  the  time  of  weaning. 

After  fattening,  20th  December,  the  7  swine  weighed  2101.0 
Before       "  6th  September  "       169.8 

Increase  In  104  days.  4''9.2  lbs. ;  or  fcr  head . . .     68.8 
Increase  per  day  and  per  head 0.073 


THE   HOa. 


4<59 


In  the  course  of  the  104  days,  there  were  consumed  : 


lbs. 

Barley 772 

Peas..  1042.8 

Potatoes. 9504 


lbs. 

equivalent  to  hay  1144 

4171 

"  8296 


Greasy  water  and  whey — quantity  not  determined  •  •  8833.6 
So  that  with  the  provender  equivalent  to  100  lbs.  of  hay,  4.91  lbs.  ol 
live  weight  had  been  produced. 

These  seven  porkers,  slaughtered,  yielded  : 


Hogs. 

Weight 
alive. 

"Weight  after 
bleeding. 

Weight  of 
the  blood. 

Weight  of 
the  porkers 

without 
heads  or  feet. 

\ 

Weight  of 

heads  and 

Oflfal. 

1 
2 
8 
4 
5 
6 
7 

lbs. 

323.0 

259.0 

283.0 

316.0 

264 

259.6 

393.8 

lbs. 

312 

248 

272 

306 

257.4 

250.8 

876.2 

lbs. 

11 

11 

11 

11 
6.6 
8.8 

17.6 

lbs. 

268.0 

208.4 

208.2 

263.2 

220.0 

213.4 

821.2 

lbs. 
44.0 
39  6 
63-8 
41.8 
37-4 
37.4 
65.0 

2098.6 

" 

1702.6 

" 

It  must  be  admitted  that  these  animals  had  increased  both  in  flesh 
and  in  fat ;  but  in  spite  of  this,  the  experiment  appears  to  be  un- 
favorable to  the  opinion  that  fat  in  animals  is  the  efiect  of  direct  as- 
similation of  the  substance.  The  whole  increase  in  weight  of  the 
seven  porkers  had  been  409.2  lbs. ;  supposing  27  per  cent,  of  fat  in 
this  increase,  its  amount  must  have  been  110.4  lbs.  in  all ;  but  the 
food  consumed  did  not  contain  more  than  57.4  lbs.  It  would  there- 
fore be  necessary  to  admit  that  the  food  which  had  not  been  taken 
into  the  account  had  contained  as  many  as  53.0  lbs.  of  fatty  matter, 
which  I  own  does  not  appear  to  me  probable.  But  no  definitive 
conclusion  can  be  drawn  from  the  circumstance,  owing  to  the  actual 
state  of  fatness  of  the  animals,  when  they  were  specially  put  up  to 
fatten,  not  having  been  ascertained  ;  perhaps  the  absolute  quantity 
of  fat  already  accumulated  is  greater  at  this  time  than  is  generally 
supposed. 

I  find,  for  instance,  that  a  young  porker  of  196.9  lbs.,  killed  at 
the  time  when  he  might  have  been  put  up  to  fatten  specially,  yielded 
as  many  as  25.3  per  cent,  of  fat. 

The  following  are  the  data  afforded  by  the  fattening  of  the  farm 
porkers  for  1842  : 

Nine  porkers,  from  thirteen  to  fifteen  months  old,  and  already  in 
good  condition,  were  put  upon  the  full  fatting  allowance  on  the  1st 
of  October,  on  which  day  they  weighed  : 

lbs. 
1940 
November  28th,  after  having  been  bled,  they  weighed. .  .2807.8 


Increase  In  58  days  per  head  and  per  day. 
40 


470 


THE   HOG. 


In  the  course  of  fifty-eight  days  the  hogs  had  consumed  : 

lbs.  lbs. 

Eye. 770  equivalent  to  hay  1141.8 

Peas  1802  "  6209 

Potatoes 4796  "  1861 

Greasy  water  and  whey  undetermined 8221.8 

The  nine  animals  gave  1746.8  lbs.  of  meat,  fat  and  lean,  or  75.'3 
per  cent,  of  their  weight  as  they  stood  alive  ;  besides  which,  141.9 
say  142  lbs.  of  lard  were  obtained  from  the  internal  parts.  No\n 
supposing  that  in  the  increase  of  weight  obtained  in  the  course  o: 
fifty-eight  days,  the  fat  were  to  be  represented  by  29  per  cent.,  the 
fat  fixed  would  amount  to  100.1  lbs. ;  while  the  whole  of  the  fatt} 
substances  contained  in  the  food  consumed  would  not  amount  to  mon 
than  59.6  lbs.  It  would  therefore  be  imperative  to  us,  did  we  main 
tain  that  all  the  fat  was  obtained  ready  formed  from  without,  to  sup 
pose  that  the  whey  and  dish  washings  administered  in  indeterminate 
quantity,  had  introduced  40.5  lbs.  of  fat  into  the  bodies  of  the  animals 
Some  experiments  which  are  going  on  at  Bechelbronn  at  this  mo 
ment  will,  I  trust,  settle  the  question  definitively  as  to  whether  during 
the  fatting  of  hogs  and  other  animals  there  is  any  formation  of  fat  a 
the  cost  of  the  starch  and  sugar  of  the  food. 

The  observations  which  I  have  .made  on  the  fattening  of  hogs  ma] 
be  summed  up  in  these  terms  : 


2  b 

^ 

1i 

S"^ 

fe 

-§^1 

§ag 

11 

I' 

5 

Iff 

<3"S 

Duration  of  the  experi- 
ment 

lbs. 

lbs. 

lbs. 

Months. 

Months. 

Days. 

5.1 

0.440 

8.58 

1 

11 

18^ 

0.836 

18.21 

9 

u 

21 

15.7 

1.958 

12.52 

9* 

t« 

20 

u 

1.254 

" 

12 

t4 

« 

11.6 

0.572 

4.91 

15 

(( 

104 

15.4 

0.660 

4.21 

14 

" 

68 

The  allowance  to  the  hogs  in  the  preceding  observations  was  al 
ways  abundant.  To  determine  the  quantity  of  potatoes  consume( 
each  day  by  a  hog  in  full  growth,  and  whose  weight  was  known, 
had  him  weighed  at  intervals,  as  well  as  the  potato  ration,  place* 
before  him  at  will,  which  he  ate  daily,  and  found  that  when  h 
weighed : 


Ter  100  of  th« 


Iba.  lbs.  Iba,        liv 

188    he  ate    11    equiv.alent  in  hay  to    8.4 


145 
160.5 

184.8 


18.2 
15.4 
17.6 


4.' 
4.8 
6.6 


2.52 


30.1 
8.02 


THE    HOG.  471 

To  these  observations  on  the  keep  and  fatting  of  horned  cattle, 
horses,  and  hogs,  I  would  gladly  have  added  remarks  of  like  extent 
on  the  growth  and  fattening  of  sheep  ;  unfortunately,  I  have  only 
been  able  to  obtain  very  imperfect  niformation  on  this  branch  of 
rural  economy.  I  have,  however,  sought  to  ascertain  approximately 
the  relations  which  exist  between  the  weight  of  a  young  animal,  the 
food  consumed,  and  the  increase  in  live  weight,  by  means  of  the  fol- 
lowing experiment : 

Two  sheep  six  months  old  weighed  together 184.2  lbs. 

Sixteen  days  afterwards  they  weighed 151.8 

Total  increase 1T.6 

Increase  per  day,  per  head 0.55 

In  the  sixteen  days  the  two  sheep  ate  : 

Hay 22.0  =  Hay 22.0 

Potatoes 53.3  —Hay 16.9 

88.9 

Or  per  head  in  hay 19.45 

Or  per  head  per  day 1.21 

^  This  would  give  us  about  2.9  of  hay  provender  per  cent,  of  the 
Kve  weight,  so  that  a  ration  which  should  be  represented  by  100  of 
hay  would  be  followed  by  an  increase  on  the  weight  of  a  sheep  of 
six  months  old  of  27.7  per  cent. 

^  Vr.   OF  THE  PRODUCTION  OF  MANURE. 

The  forage  consumed  on  the  farm  being  the  source  of  the  manure 
produced  there,  it  would  seem  that  it  must  be  easy  to  calculate  the 
value  of  all  that  comes  from  the  stables  and  cow-houses  day  after 
day.  I  do  not  mean  the  mass  or  weight  of  the  dejections  here,  for 
it  is  certain  that  the  more  or  less  watery  nature  of  the  food  mate- 
rially influesces  the  weight  of  the  dung  produced  ;  and  if  a  common 
mode  of  calculating  the  quantity  of  dung  by  merely  multiplying  the 
weight  of  food  consumed  by  three  be  correct  in  some  cases,  it  is 
very  far  from  the  truth  in  others.  The  dung  produced  on  the  farm 
must  be  calculated  on  different  gTOunds  from  this  ;  and  without  pre- 
tending to  any  degree  of  accuracy  which  is  really  unattainable,  it  is 
still  very  possible  to  get  at  the  quantity  of  azote  which  is  contained 
in  the  litter  and  in  the  dejections,  so  as  to  be  able  to  refer  to  a  stand- 
ard the  quantity  of  manure  made. 

Were  not  the  azotized  principles  of  the  food  partly  exhaled  by 
animals,  the  whole  quantity  not  appearing  in  the  excretions,  it  is  ob- 
vious that  it  would  suffice  to  have  ascertained  the  quantity  of  azote 
contained  in  the  food,  to  be  in  a  condition  to  decide  on  that  con- 
tained in  the  dung  added  to  the  litter.  But  this  cannot  be  done  ;  to 
be  convinced  of  the  fact,  it  is  enough  to  take  the  least  complex  case, 
that  of  a  full-grown  horse,  receiving  as  his  allowance  per  day  : 

Hay 22  lbs,  containing  1775.8  grains  of  azote. 

Oats  11  "  1389.4  " 

Straw 11  "  808.T  " 

Litter.....  8.8  "  108.0  ♦* 

Azote.... 8581.4  ::    ' 


4T2  THE  HOG. 

Now  assumiDg  2  per  cent,  as  the  contents  in  azote  of  dry  farm- 
yard dung,  we  see  that  the  food  consumed  by  the  horse,  speaking 
theoretically,  might  or  should  form  25.5  lbs.  of  dry  manure.  But 
we  have  seen  that  a  horse  or  cow  will  exhale  from  355.0  to  41 6.8 
grs.  of  azote,  which  is  all  derived  from  the  food,  and  is  consequ  ntly 
lost  to  the  dung-heap.  Now  3859  grs.  of  azote  represent  2.75  lbs. 
of  dry  manure  ;  so  that  the  dry  dung  produced  by  the  horse  kept  in 
the  stable,  will  be  reduced  from  25.5  lbs.  to  23.1  lbs.  In  the  course 
of  a  year,  upon  this  calculation,  the  azote  exhaled  will  diminish  the 
weight  of  dry  dung  produced  by  one  horse  by  a  quantity  equal  to 
1045  lbs. 

The  azote  of  the  food  of  a  cow  is  still  more  considerable  in  quan- 
tity, and  the  loss  to  the  dunghill  proportionally  larger  ;  inasmuch  as 
to  the  amount  she  exhales,  must  be  added  all  that  goes  to  constitute 
the  milk  she  gives.  Practical  men,  without  pretending  to  get  at 
the  cause  of  the  thing,  have  long  been  aware  of  the  fact,  that  a  cow 
produces  less  dung  than  a  horse ;  and  the  truth  of  this  is  readily 
demonstrated  on  scientific  grounds.  Suppose  a  cow,  consuming  the 
equivalent  of  33  lbs.  of  hay,  and  giving  about  17  pints  of  milk  per 
day: 

33  lbs.  of  hay  contain 2670  grs.  of  aiote, 

44    "        straw  for  litter  contain.     128         " 

Azote 2793  —  19.8  lbs.  of  dung  supposed  to  be  dry. 

But  in  the  24  hours,  there  have  been  of 

Azote  exhaled  ... 8S5.9  grains,  and  of 

Azote  in  17  pints,  or  22.7  lbs  of  milk  carried  ofl^ 802.7  grains. 

1188.6  —  S  8  of  dry  dung: 

The  33  lbs.  of  hay  digested  by  the  cow,  consequently,  the  litter 
added,  have  only  produced  8.8  of  dry  dung.  The  azote  of  the  food, 
of  which  we  find  no  account  in  the  dejections,  amounts  per  annum 
to  nearly  30  cwts.,  (3300  lbs.,)  the  deficiency  in  the  case  of  the 
horse  amounting  to  no  more  than  1045  lbs.,  (9  cwts.  1  qr.  9  lbs.) 

The  estimation  of  the  dung  produced  by  growing  animals,  pre- 
sents several  special  difficulties,  inasmuch  as,  besides  the  azote 
exhaled  from  the  lungs,  there  is  the  quantity  that  is  fixed  in  the  liv- 
ing body. 

In  one  of  the  experiments  which  I  have  related,  it  appears  that  a 
calf  six  months  old,  consuming  : 

Hay  9.6  lbs.  containing 10C9.S  azote. 

Discharged  by  its  dejections 88S.8    " 

Azote  fixed  or  exhaled  in  24  hours 281.5    " 

The  azote  lost  to  the  manure  by  the  fixing  of  azote  is  therefore 
very  considerable,  in  the  case  of  young  animals  as  well  as  of  milch- 
kine.  We  find,  for  example,  that  for  every  100  lbs.  weight  of  hay 
consumed  : 

A  horse  supplies  the  equivalent  of  61  lbs.  of  dry  standard  dung^ 

A  milch-cow 82  "  " 

A  calf  of  six  months ...40  «  •* 


THE    HOG.  4*73 

To  estimate  with  any  rigoi*  the  quantity  of  azotized  manure  which 
ought  to  result  from  the  forage  consumed  on  the  farm,  it  were  ne- 
cessary to  know  the  proportion  of  azote  contained  in  the  bodies  of 
all  the  animals  entertained  upon  it.  Having  the  increase  of  weight 
that  occurred  in  the  stable,  cow-house,  pig-stye,  and  poultry-yard,  we 
should  then  be  in  a  condition  to  Know  the  precise  quantity  of  dung 
wiiich  it  would  be  necessary  to  retrench  from  that  which  the  forage 
ought  to  have  produced,  had  there  been  no  production  of  animal 
matter,  had  the  whole  of  the  azote  of  the  food  passed  through  the 
live-stock  to  the  dung-hill.  Unfortunately,  we  have  no  very  precise 
data  by  which  we  might  calculate  the  quantity  of  azote  contained  in 
a  living  animal.  I  shall,  nevertheless,  endeavor  to  apply  such  as 
we  possess. 

From  a  few  practical  experiments,  and  the  information  at  my 
command,  I  admit  that  the  following  substances  in  their  usual  state 
contain  per  cent. : 

Moisture.       Dry  matter.  Salts.  Azote. 

Beef-flesh 77  28  1.0  8.5 

Veal " 

Blood  80  20  0.9  8.0 

Skin 60  40  1.0  7.2 

Hair 9  81  2.0  13.8 

Horn 9  91  0.7  14.4 

Beef  bones  (tibia) 80  70  " 

An  entire  skeleton 86  64  85.0  5.2 

Brain,  intestines,  &c  81  10  1.0  2.9 

Fat  freed  from  skin 20  80  "  1-9 

These  data  applied  to  the  various  parts  which  enter  into  the 
constitution  of  the  animals  which  up  to  this  point  have  engaged 
our  attention,  we  should  have  for  the  quantity  of  azote  per  cent. 

contained  : 

In  homed  cattle 8.47 

In  the  horse 8.64 

Inthehog 8.80 

In  the  sheep 8.66 

Average 8.64 

For  every  100  lbs.  of  live  weight  produced  on  the  farm,  conse- 
quently, we  may,  without  probably  being  a  great  way  from  the  truth, 
presume  that  there  has  been  3.6  of  azote  fixed,  azote  obtained  from 
the  forage,  and  which,  consequently,  cannot  go  to  the  dung  heap  ;  in 
other  words,  every  100  lbs.  of  live  weight  produced,  deprive  the 
establishment  of  180  lbs.  of  dry  standard  dung,  or  nearly  18  cwts. 
of  moist  farm-yard  dung.* 

We  may  be  allowed,  therefore,  to  entertain  the  hope  that  we  shall 
one  day  be  able,  from  the  quantity  of  forage  consumed  upon  a  farm, 
to  calculate  the  actual  quantity  of  manure  which  we  shall  have  at 
our  disposal.  To  arrive  at  this  result,  it  would  indeed  only  be  ne- 
cessary to  subtract  the  manure  represented  by  the  azote  exhaled 
from  and  fixed  in  the  bodies  of  the  stock,  from  the  amount  of  azo- 

•  The  discussion  will  undoubtedly  extend  by  and  by  to  phosphoric  acid.  I  shall 
only  say  at  this  time,  that  from  the  results  obtained  in  the  case  of  a  pig,  tlie  phos- 
phoric add  appears  to  bo  in  tho  proportion  of  from  2  to  3  per  cent,  of  the  live  weight 

40* 


474  THE    HOG. 

tized  manure  represented  by  the  whole  quantity  of  forage,  were  it 
to  be  used  immediately.  To  obtain  results  of  any  accuracy,  how 
ever,  it  were  necessary  to  possess  data  both  more  numerous  and 
more  precise  than  any  we  have  at  present.  This  perfection  of  co- 
efficients must  be  viewed  as  an  affair  for  the  future ;  agricultura 
science  has  almost  every  thing  to  create. 

In  estimating  the  quantity  of  manure  from  the  forage  consumed, 
it  has  been  supposed  that  there  is  no  loss.  With  reference  to  the 
stall  or  cow-house,  a  careful  husbandman  may  approach  this  perfec- 
tion, by  doing  almost  the  contrary  of  all  that  is  usually  done  now-a- 
days  ;  i.  e.  by  taking  every  precaution  against  waste  ;  but  it  is  obvi- 
ous that  in  so  far  as  the  stable  is  concerned,  there  must  always  be  a 
considerable  and  inevitable  loss  ;  all  that  falls  upon  •  highways  and 
byways  is  irretrievably  gone.  It  is,  indeed,  matter  of  ordinary  cal- 
culation that  in  consequence  of  their  work  out  of  doors,  the  horses 
upon  a  farm  do  not  afford  more  than  about  two  thirds  of  the  dung 
which  ought  to  be  obtained  from  the  provender  consumed.  Some 
experiments  made  in  the  stables  at  Bechelbronn  show  that  the  loss 
in  this  way  may  amount  to  one  quarter  of  the  whole  amount  of 
dejections  ;  still,  as  the  animals  are  for  the  major  part  engaged  on 
the  land  of  the  farm,  it  is  obvious  that  what  falls  there  is  by  no 
means  lost.  To  supply  my  reader  with  definite  sums  from  a  partic- 
ular instance,  upon  which  he  may  fix  his  mind,  I  shall  state  for  his 
information  that  in  the  course  of  1840-41,*  my  stock  at  Bechelbronn, 
consisting  of  sixteen  head  of  cattle,  eleven  calves,  twenty-seven 
horses,  and  (?)  hogs,  consumed  333,579  lbs.  or  148  tons,  18  cwts. 
1  qr.  15  lbs.  of  forage,  containing  6925  lbs.  of  azote,  and  produced 
upon  their  original  weight  20,821  lbs.  of  flesh,  fat  and  milk,  contain- 
ing with  the  addition  of  a  calculated  quantity  for  loss  from  out  of 
door  droppings,  exhalation  by  the  lungs,  &c.,  2631  lbs.  of  azote. 
The  forage  and  litter,  from  their  contents  in  azote,  ought  to  have 
produced  about  15,356  cwt.  of  moist  farm-yard  dung;  they,  however, 
produced  no  more  than  9522  cwt. ;  and,  in  fact,  we  see  that  there 
had  been  a  consumption  of  azote  by  arrest  within  the  bodies  of  the 
stock,  by  exhalation  from  their  lungs,  and  by  loss,  amounting  to  2631 
lbs. ;  by  an  equivalent  quantity  of  dung,  therefore,  had  the  absolute 
produce  necessarily  been  diminished. 

Thaer  allows  that  articles  of  dry  forage  and  litter  double  their 
weight  in  becoming  converted  into  dung.  The  statement  which  I 
have  just  made  agrees  on  the  whole  pretty  well  with  this  estimate. 
In  our  cow-house  ration,  one  half  only  is  generally  hay,  the  other 
half  consists  of  roots  and  tubers.  The  dry  forage  and  litter  conse- 
quently amount  to  4G60  cwt.  which  according  to  Thaer  ought  to 
become  changed  into  9320  cwt.  of  dung,  a  number  not  very  wide  of 
that  to  which  we  have  come.  Sinclair  reckons  the  dung  of  the  cow- 
house at  four  times  the  weight  of  the  litter,  a  view  which  neither 
accords  with  Thaer's  estimate  nor  with  our  experience. 

I  think  it  altogether  unnecessary  to  insist  on  the  importance  tt 

*  Twelve  months  I  presume.— Ekg.  Ed. 


METEOROLOGY. ^TEMPERATURE  415 

the  farmer  of  a  foreknowledge  of  the  quantity  of  manure  which  he 
may  reasonable  calculate  on  obtaining  from  a  known  weight  of  forage 
consumed  upon  his  premises.  Of  the  various  methods  proposed  foi 
arriving  at  this  information,  that  which  I  have  employed,  and  which 
is  based  on  ascertaining  the  amount  of  azote,  appears  to  me  the  best 
calculated  to  supply  satisfactory  results,  particularly  when  experience 
shall  have  corrected  or  confirmed  the  numbers  which  I  have  adopted 
as  the  elements  of  my  calculations. 

I  have  already  said  that  any  supplementary  forage,  or  forage 
added  to  that  which  is  indispensable  to  the  production  of  manure, 
generally  acquires,  by  the  fact  of  its  conversion  into  power  or  into 
exportable  substances,  a  value  superior  to  that  which  it  could  have 
had  of  itself  in  the  market  place.  This  additional  forage  is  that 
fraction  of  the  provender,  the  azote  of  which  figures  in  the  statements 
that  have  just  been  made  as  azote  exhaled  or  assimilated  and  fixed. 
We  find,  in  fact,  in  representing  this  forage  which  is  lost  to  the 
dung-heap,  but  gained  to  power  and  exportable  articles,  that  in  the 
stall,  100  lbs.  of  hay  yield  8.6  lbs.  of  live  weight,  and  40.8  lbs.  of 
milk,  and  that  in  the  hog-stye,  100  lbs.  of  hay  yield  21  of  living 
weight.  In  the  stable,  again,  the  azote  fixed,  exhaled,  or  lost  amounte 
to  nearly  1540  lbs.,  represented  by  about  1218  cwts.  of  hay,  which 
have  yielded  1504  lbs.  of  live  weight,  due  in  great  part  to  the  birth 
and  growth  of  foals,  in  addition  to  the  force  represented  by  8370 
days'  work. 


CHAPTER  IX. 

METEOROLOGICAL   CONSTDERA.TIONS. 
g  1.   TEMPERATURE. 

The  phenomena  of  vegetation  are  always  accomplished  under  the 
influence  of  a  certain  temperature.  If,  in  addition,  the  concurrence 
of  light,  air,  moisture,  and  various  inorganic  substances,  be  required, 
it  is  still  perfectly  certain  that  all  of  these  agents  only  contribute  to 
the  development  of  a  plant  when  they  are  assisted  by  a  due  measure 
of  heat,  variable  with  reference  to  the  different  vegetable  species, 
and  comprised  within  limits  that  are  rather  far  apart,  but  essential. 
Germination,  for  example,  takes  place  at  a  temperature  a  few  degrees 
above  the  freezing  point  of  water,  38°  or  39°  P.,  and  at  one  indica- 
ted by  100°  or  120°  of  the  same  scale.  The  forests  of  tropical 
countries  thrive  in  a  hot,  moist  atmosphere,  which  often  marks  up- 
wards of  100°  P. ;  and  I  met  with  a  saxifrage  upon  the  Andes  at 
an  elevation  of  15,748  feet  above  the  level  of  the  sea,  beyond  the 
line  of  perpetual  snow,  and  very  near  the  line  of  perpetual  con* 
gelation. 

Some  families  of  plants  require  a  temperature  not  only  high,  but 
that  never  falls  bolow  a  certain  very  limited  degree  ;  the  majority 


476  METEOROLOGY. ^TEMPERATURE 

of  the  intertropical  plants  are  in  this  predicament.  There  are  others 
which,  imperatively  requiring  a  high  temperature  for  their  growth 
and  perfection,  nevertheless  suspend  their  powers  during  the  winter, 
and  bear  without  detriment  degrees  of  cold  of  great  intensity  : 
among  the  number  may  be  cited  the  larch-pine,  which  abounds  in 
Siberia,  and  stands  the  utmost  rigors  of  its  climate,  where  the 
thermometer  at  mid-winter  frequently  falls  to  30°  and  even  40"  be- 
low zero, F. 

The  meteorological  habitudes  or  dispositions  of  plants  being  ex- 
tremely various,  it  follows,  that  the  geographical  distribution  of 
plants  is  a  consequence  of  the  distribution  of  heat  over  the  surface 
of  the  globe — of  climate. 

The  earth  we  inhabit  appears  to  have  a  heat  proper  to  itself ;  it  is 
a  heated  body  in  progress  of  cooling.  It  is  found,  in  fact,  that  as 
the  centre  of  the  earth  is  approached,  as  mines  penetrate  more 
deeply  below  its  surface,  the  temperature  increases.  Below  a  very 
limited  distance  from  the  surface,  the  temperature  ceases  to  be 
affected  by  variations  in  the  temperature  of  the  general  atmosphere  ; 
from  the  point  of  invariable  temperature  the  subterranean  heat  in- 
creases uniformly  at  the  rate  of  1°  cent.  (1.8°  Fahr.)  for  every  101 
feet  of  descent. 

The  depth  at  which  the  point  or  stratum  of  invariable  temperature 
is  met  with,  varies  in  different  places,  and  is  mainly  affected  by  the 
extent  of  the  thermometrical  variations  in  the  superincumbent  air  in 
tlie  course  of  the  year.  In  the  higher  latitudes,  consequently,  the 
depth  is  very  considerable  ;  at  Paris,  for  example,  M.  Arago  has 
found  that  a  thermometer,  buried  at  264  feet  under  the  surface,  does 
not  reman  absolutely  stationary.  In  climates  of  greater  constancy, 
as  may  be  conceived,  the  layer  of  invariable  temperature  will  be 
found  much  nearer  the  surface  ;  were  the  temperature  of  the  air  in- 
variable, the  layer  of  invariable  temperature  would  necessarily  be- 
found  at  the  surface  of  the  ground.  In  countries  under  and  close  to 
the  equator,  this,  in  fact,  is  found  to  be  the  case.  From  a  series  of 
observations  which  I  made  in  So  ith  America,  between  the  2d  paral- 
lel of  southern  and  the  11th  of  northern  latitude,  I  found  that,  near 
the  line,  the  layer  of  invariable  temperature  is  found  nearly  at  the 
surface  ;  the  thermometer,  placed  in  a  hole  about  one  foot  deep, 
under  the  shade  of  an  Indian  cabin,  or  a  shed,  does  not  vary  by  more 
than  from  one  tenth  to  two  tenths  of  a  degree  Cent. 

It  was  probably  under  the  influence  of  "the  internal  or  proper  heat 
of  the  globe,  according  to  M.  de  Humboldt,  that  the  same  species 
of  animals  which  are  now  confined  to  the  torrid  zone,  inhabited,  in 
former  and  remote  ages,  the  northern  hemisphere,  covered  as  it  then 
was  by  arborescent  ferns  and  stately  palms.  It  is  easy  to  imagine 
how,  as  the  surface  of  the  earth  cooled,  the  distribution  of  climates 
became  almost  exclusively  dependent  on  the  action  of  the  solar  rays, 
and  how  also  those  tribes  of  plants  and  of  animals,  the  organization 
of  which  required  a  higher  temperature  and  more  equable  climate 
gradually  died  out  and  disappeared.* 

•  Huml)oldt'»  Central  Aria,  r.  lli,  p.  9a 


METEOROLOGY. — TEMPERATURE.  47 1 

111  the  state  of  stability  to  which  the  surface  of  the  globe  appears 
actually  to  have  attained,  the  sun  must  be  considered  as  the  agent 
which  most  directly  iniiueiicos  the  temperature  of  our  atmosphere. 
The  length  of  the  day,  the  number  of  hours  during  which  the  sun  is 
above  the  horizon,  coupled  with  the  height  to  which  he  ascends, 
such  is  the  cause  with  which  the  temperature  of  each  particular  lati- 
tude is  primarily  connected  ;  and,  in  looking  at  the  subject  practi- 
cally, it  is  found  to  be  so  precisely  ;  not  only  is  the  mean  tempera- 
ture of  the  year  dependent  on  the  length  of  the  days,  and  the  meridian 
altitude  of  the  sun,  but  the  mean  temperature  of  each  month  in  the 
year  is  essentially  connected  with  the  same  circumstances.  In  the 
northern  hemisphere,  the  temperature  rises  from  about  the  middle 
of  January,  slowly  at  first,  more  rapidly  in  April  and  May,  to  reach 
its  maximum  point  in  July  and  August,  when  it  begins  to  fall  again 
until  mid-January,  when  it  is  at  its  minimum. 

The  highest  mean  annual  temperature  is,  of  course,  observed  in 
the  neighborhood  of  the  equator  ;  between  0°  and  10°  or  12°  of  lati- 
tude on  either  side,  at  the  level  of  the  sea,  where  besides  the  equal- 
ity of  day  and  night,  the  sun,  always  elevated,  passes  the  zenith 
twice  a  year.  The  observations  that  have  been  made  up  to  this 
time,  lead  us  to  conclude  that  this  temperature  oscillates  between 
260  and  29"  cent.  ;  78.8o  and  84.2°  Fahr.  _ 

Did  the  earth  present  unvarying  uniformity  of  surface,  not  only 
with  reference  to  elevation  but  to  constitution,  so  that  the  power  of 
absorbing  and  of  radiating  heat  should  be  everywhere  alike,  the  cli- 
mate of  a  place  would  depend  almost  entirely  on  its  geographical 
position ;  the  points  of  equal  temperature  would  be  found  on  the 
same  parallels  of  latitude,  or,  to  employ  the  happy  expression  intro- 
duced by  M.  de  Humboldt,  the  isothermal  lines  would  all  be  parallel 
with  the  equator.  But  the  surface  of  our  planet  is  covered  with  un- 
dulations and  asperities,  which  cause  its  outline  to  vary  to  infinity  ; 
and  then  the  soil  is  dry,  or  swampy  ;  it  is  a  moving  desert  of  sand, 
or  covered  with  umbrageous  and  impenetrable  forests  ;  and  all  this 
causes  corresponding  varieties  in  climate,  for  the  surface  becomes 
heated  in  different  degrees  as  it  is  in  one  or  other  of  these  condi- 
tions. Another  very  important  consideration  is,  that  the  surface  is 
a  continent,  or  an  island  in  the  ocean  :  the  climate  of  a  country,  or 
a  district,  is  vastly  influenced  by  its  proximity  to  or  distance  from 
the  sea.  The  difficulty,  the  slowness,  with  which  such  a  mass  of 
liquid  as  the  ocean  becomes  either  heated  or  cooled,  is  the  cause  of 
the  temperate  character  both  of  the  summers  and  winters  of  the 
shores  it  bathes,  and  the  islands  of  moderate  dimensions  it  surrounds. 
As  we  penetrate  great  continents  from  the  sea-board,  we  find  that 
the  temperature  both  of  summer  and  winter  becomes  extreme,  and 
the  difference  between  the  mean  summer  and  mean  winter  tempera- 
ture is  great ;  and  again  we  find,  that  places  which  have  considera- 
bly different  latitudes,  have  still  very  nearly  the  same  mean  annual 
temperature.  The  mean  temperature  of  Paris,  in  latitude  48°  50  , 
is  about  51.4°  F.  j  that  of  London,  in  lat  51°  31',  is  50.7°  F.  j  that 


478  METEOROLOGY. TEMPERATURE. 

of  Dublin,  in  lat.  53o  23',  is  49 .l^  F. ;  and  that  of  Edinburgh,  in  lai 
550  57',  is  48.40  F. 

An  island,  a  peninsula,  and  the  sea  shore,  consequently,  enjoy  a 
more  temperate  and  equable  climate — the  summers  less  sultry,  the 
winters  more  mild.  On  the  shores  of  Glenarm,  in  Ireland,  in  lati- 
tude 550,  the  myrtle  vegetates  throughout  the  year  as  in  Portugal ; 
it  rarely  freezes  in  winter  ;  but  the  heat  of  summer  does  not  suffice 
to  ripen  the  grape.  Under  the  very  same  parallel,  however,  at 
Konigsberg,  in  Prussia,  they  experience  a  cold  of  17°  and  18°  below 
zero  of  Fahrenheit's  scale  in  the  winter.  The  ponds  and  little  lakes 
of  the  Feroe  Islands,  although  situated  in  N.  lat.  62°,  never  freeze, 
and  the  mean  winter  temperature .  is  very  nearly  40°  F.  On  the 
coasts  of  Devonshire,  in  England,  the  winters  are  so  mild,  that  the 
orange-tree,  as  a  standard,  will  there  carry  fruit ;  and  the  agave  has 
been  seen  to  flourish,  after  having  lived  both  winter  and  summer, 
lor  twenty-eight  years,  in  the  open  air,  uninjured. 

One  of  the  grand  characteristics  of  what  may  be  called  a  mari- 
time climate,  is  the  less  difference  which  occurs  between  the  tem- 
perature of  summer  and  that  of  winter.  At  Edinburgh,  for  instance, 
the  difference  only  amounts  to  19°  F. ;  at  Moscow,  which  is  nearly 
on  the  same  parallel,  the  difference  amounts  to  50^  F. ;  and  at 
Kasan,  (lat.  56°,)  it  is  as  much  as  56.3o  F. 

The  influence  of  extensive  continents,  or  remoteness  from  the 
sea-board,  does  not  seem  merely  to  render  a  climate  extreme,  in- 
creasing at  once  the  heat  of  summer  and  the  cold  of  winter.  The 
collective  observations  on  temperature,  made  in  Europe  and  in  Asia, 
show  that  the  mean  annual  temperature  decreases  as  we  penetrate 
more  into  the  interior  of  continents  towards  the  east.  Humboldt 
ascribes  this  diminution  of  temperature  partly  to  the  refrigerating 
action  of  the  prevailing  winds.  While  the  mean  annual  temperature 
of  Amsterdam  (N.  lat.  52°  22')  is  49.6°  F. ,  that  of  Berlin  (N.  lat. 
520  31')  is  47.40  F. ;  that  of  Copenhagen,  (N.  lat.  55o  41')  is  46.7° 
F.  ;  and  that  of  Kasan  (N.  lat.  55°  48')  is  but  35.9o  F. 

The  highest  temperi\ture  which  has  yet  been  registered,  as  occur- 
ing  in  the  open  air,  appears  to  have  been  observed  by  Burckhardt,  in 
Upper  Egypt ;  the  thermometer  indicated  47.5°  cent.,  upwards  of 
118^  F.  The  lowest  was  seen  by  Captain  Back,  in  North  America, 
when  the  thermometer  fell  to  —  .56^  cent.,  68.°  F.  below  zero. 

I   II.   DECREASE    OF    TEMPERATURE    IN   THE     SUPERIOR   STRATA   OP   THE 
ATMOSPHERE. 

The  temperature  rises  rapidly  as  we  ascend  in  the  atmosphere  ; 
places  among  the  mountains  always  possess  a  climate  more  severe 
as  they  are  higher  above  the  level  of  the  sea.  Even  under  the 
equator,  height  of  position  modifies  the  seasons  so  much,  that  the 
hamlet  of  Antisana,  which  is  within  one  degree  of  south  latitude,  but 
which  is  upwards  of  13,000  feet  above  the  sea  level,  has  a  mean 
temperature  which  does  not  differ  much  from  that  of  St.  Peters- 
burgh.    Near  it,  but  at  a  still  greater  height,  the  summit  of  Cyambe, 


METEOROLOGY. — ^TEMPERATURE.  479 

covered  by  an  immense  mass  of  everlasting  snow,  is  cut  by  the 
equinoctial  line  itself. 

The  cold  which  prevails  among  lofty  mountains,  is  ascribed  to  the 
dilatation  which  the  air  of  lower  regions  experiences  in  its  upward 
ascent,  to  a  more  rapid  evaporation  under  diminished  pressure,  and 
to  the  intensity  of  nocturnal  radiation. 

Places  which  are  situated  upon  the  same  mountain-chain,  nearly 
in  the  same  latitude,  and  at  the  same  height,  have  often  very  differ- 
ent climates.  The  temperature  which  would  be  proper  to  a  place 
perfectly  isolated,  is  necessarily  modified  by  a  considerable  number 
of  circumstances.  Thus  the  radiation  of  heated  plains  of  considera- 
ble extent,  the  nature  of  the  color  of  the  rocks,  the  thickness  of  the 
forests,  the  moistness  or  dryness  of  the  soil,  the  vicinity  of  glaciers, 
the  prevalence  of  particular  winds,  hotter  or  colder,  moister  or  drier, 
the  accumulation  of  clouds,  &c.,  are  so  many  causes  which  tend  to 
modify  the  meteorological  conditions  of  a  country,  whatever  its 
mere  geographical  position.  The  neighborhood  of  volcanoes  in  a 
state  of  activity  does  not  appear  to  affect  the  temperature  sensibly  : 
thus  Purace,  Pasto,  Cumbal,  which  have  flaming  volcanoes  towering 
over  them,  have  not  warmer  climates  than  Bogata,  Santa  Eosa,  De 
Osos,  Le  Param  de  Herve,  &c.,  situated  on  sand-stone  or  syenite. 

From  the  whole  series  of  observations  which  I  had  an  opportunity 
of  making  on  the  Cordilleras,  it  appears  that  one  degree  of  tempera- 
ture, cent.,  1.8°  F.,  corresponds  to  195  metres,  or  649.4  feet  of 
ascent  among  the  equatorial  Andes.  In  Europe,  it  has  been  ascer- 
tained that  the  decrease  of  temperature  in  ascending  mountains,  is 
more  rapid  during  the  day  than  during  the  night — during  summer 
than  during  the  winter ;  for  example,  between  Geneva  and  Mount 
St.  Lernard,  to  have  the  Fahrenheit  thermometer  fall  one  degree,  it 
is  necessary  to  ascend  : 

In  spring 826.1  feet. 

In  summer 886.6 

In  autumn • 882.2 

In  winter. 422.2 

It  sometimes  happens,  however,  that  in  winter,  in  a  zone  of  no 
great  elevation,  the  temperature  increases  with  the  elevation — a  fact 
which  Messrs.  Bravais  and  Lottin  observed  in  the  70°  of  N.  lat.,  in 
calm  weather  ;  at  an  elevation  between  1312  and  1640  feet,  the  rise 
amounted  to  as  many  as  6°  centigrade,  10.8°  Fahrenheit. 

In  no  part  of  the  globe  is  the  diminution  of  temperature,  occasion- 
ed by  a  rise  above  the  level  of  the  sea,  more  remarkable  than  among 
equatorial  mountain  ranges  ;  and  it  is  not  without  astonishment  that 
the  European,  leaving  the  burning  districts  which  produce  the  banana 
and  cocoa-tree,  frequently  reaches,  in  the  course  of  a  few  hours,  the 
barren  regions  which  are  covered  with  everlasting  snow.  "  Upon 
each  particular  rock  of  the  rapid  slope  of  the  Cordillera,"  says  M. 
de  Humboldt,  "  in  the  series  of  climates  superimposed  in  stages,  we 
find  inscribed  the  laws  of  the  decrease  of  caloric,  and  of  the  geo- 
graphical distribution  of  vegetable  forms."* 

♦  Humboldt's  Central  Asia,  vol.  lit,  p.  286. 


480  METEOROLOGY. — TEMPERATURE. 

In  the  hottest  countries  of  the  earth,  the  summits  of  very  lofty 
mountains  are  constantly  covered  with  snow ;  in  the  elevated  and 
cold  strata  of  the  atmosphere,  the  watery  vapor  is  condensed,  and 
falls  in  the  state  of  hail  and  snow.  In  the  plain,  hail  melts  almost 
immediately ;  the  fusion  is  slower  upon  the  mountains  ;  and  for  each 
latitude  there  is  a  certain  elevation  where  hail  and  snow  no  longer 
melt  perceptibly.  This  elevation  is  the  inferior  limit  of  perpetual 
snow. 

The  accidental  causes  which  tend  to  modify  the  temperature  of  a 
climate,  also  act  in  raising  or  lowering  the  snow-line.  On  the  south- 
em  slope  of  the  Himalaya,  for  example,  the  snow-line  does  not  de- 
scend so  low  as  it  does  upon  the  northern  slope ;  and  in  Peru,  from 
14°  to  16°  of  S.  latitude,  Mr.  Pentland  found  the  perpetual  snow-line, 
at  an  elevation  of  1312  feet  higher  than  it  is  under  the  equator. 

Elevation  above  the  level  of  the  sea,  consequently,  has  the  same 
eSect  upon  climate  as  increase  in  latitude.  Upon  mountain  ranges, 
vegetation  undergoes  modification  in  its  forms,  becomes  decrepit, 
and  disappears  towards  the  line  of  perpetual  snow,  precisely  as  it 
does  within  the  polar  circle,  and  for  no  other  than  the  same  reason, 
viz.,  depression  of  temperature. 

The  constancy  and  the  small  extent  of  variation  which  occurs  in 
the  temperature  of  the  atmosphere  under  the  equator,  enables  us  to 
indicate  with  some  precision  the  point  of  mean  temperature  below 
which  there  is  no  longer  any  vegetation.  In  ascending  Chimbora- 
zo  I  met  with  this  point  at  the  height  of  15,774.5  feet,  where  the 
mean  temperature  approached  35°  F.,  and  where  consequently  the 
saxifrages,  which  root  among  the  rocks,  must  still  receive  a  temper- 
ature of  from  41°  to  43^  F.  during  the  day,  inasmuch  as  far  beyond 
the  inferior  snow-line,  at  an  elevation  of  19,685  feet  above  the  sea- 
line,  I  saw  a  thermometer  suspended  in  the  air,  and  in  the  shade 
mark  44.6°  F. 

In  considering  the  extension  of  vegetation  towards  the  polar  re- 
gions, we  discover  plants  growing  in  very  high  latitudes  in  places 
which  have  a  mean  temperature  much  below  that  which  I  believe  to 
be  the  limit  of  vegetable  life  on  the  mountains  of  the  equatorial  region. 
In  these  rigorous  climates  vegetation  is  suspended  by  the  severity 
of  the  cold  during  the  greater  portion  of  the  year  ;  it  is  only  during 
the  brief  and  passing  heat  of  summer  that  the  vegetable  world 
wakes  from  its  long  winter  sleep.  Nova  Zembla,  lat.  73°  N.,  the 
mean  temperature  of  whose  summer  is  between  34°  and  35^^  F.,  is, 
perhaps,  like  the  perpetual  snow-line  of  the  equator,  the  term  of 
vegetable  existence.  It  is  also  to  the  very  remarkable  heat  of  the 
summer  in  countries  situated  at  the  nothern  extremity  of  the  con- 
tinent of  Asia,  remarkable  if  it  be  contrasted  with  the  intensity  of 
the  winter  cold,  that  man  succeeds  in  rearing  a  few  culinary  vegeta- 
bles in  those  dreadful  climates.  At  Jakoustk,  in  62°  of  N.  lat.,  and 
where  mercury  is  frozen  during  two  months  of  the  year,  the  mean 
temperature  of  summer  is  very  nearly  64^  F.  We  have  here  as  M. 
de  Humboldt  observes,  "  a  well-characterized  continental  climate," 
examples  of  which  indeed  are  frequent  in  the  north  of  America.    At 


METEOROLOGY. GROWTH  OF  PLANTS.        48 « 

Jakoustk  wheat  and  rye  sometimes  yield  a  return  of  15  for  1,  al« 
though  at  the  depth  of  a  yard  the  soil  which  grows  them  is  cca- 
stantly  frozen.* 

The  limit  of  perpetual  snow  being  much  lower  upon  tl  e  mountains 
of  Europe  than  in  tropical  countries,  agriculture  ceases  at  a  much 
less  elevation.  At  a  height  of  6560  feet  above  the  level  of  the  sea 
the  vegetables  of  the  plain  have  almost  entirely  disappeared.  In 
Northern  Switzerland  the  vine  does  not  grow  at  an  elevation  of 
more  than  1800  feet  above  the  sea-line  ;  maize  scarcely  ripens  at  an 
elevation  of  2850  feet,  while  in  the  Andes  it  still  affords  abundant 
harvests  at  an  elevation  of  8260  feet.  On  the  plateau  or  table  land 
of  Los  Pastes,  fidds  of  barley  are  seen  at  upwards  of  10,000  feet 
above  the  level  of  the  sea ;  but  on  the  northern  slope  of  Monte  Rosa, 
in  Switzerland,  barley  fails  at  an  elevation  of  about  4260  feet ;  on 
the  southern  slope,  indeed,  it  reaches  a  height  of  about  6560  feet ; 
and  this  great  variation  in  the  ultimate  limit  of  barley  is  frequently 
observed  with  reference  to  the  same  plant  grown  upon  opposite  as- 
pects of  a  mountain  range.  The  difference  is  ascribed  to  local  in- 
fluences ;  thus,  it  is  a  well-ascertained  fact,  that  on  the  mountains 
of  the  northern  hemisphere  vegetation  reaches  a  much  higher  lati- 
tude upon  southern  than  upon  northern  exposures  ;  but  a  general 
law,  and  one  applicable  to  every  latitude,  is,  that  the  higher  we  rise 
above  the  level  of  the  sea,  the  scantier  does  vegetation  become,  the 
later  do  harvests  reach  maturity ;  but  as  the  heat  of  the  atmosphere 
increases  with  the  elevation,  it  follows  that  there  is  an  obvious  rela- 
tion between  the  time  a  crop  is  upon  the  ground  a.  d  the  mean  tem- 
perature of  the  place  or  season  where  it  grows.  We  have  still  to 
examine  this  relationship. 

^  III.    METEOROLOGICAL    CIRCUMSTANCES  UNDER  WHICH   CERTAIN 
PLANTS  GROW  IN   DIFFERENT   CLIMATES. 

In  discussing  the  conditions  of  temperature  under  which  the  va- 
rious plants  that  are  common  in  our  European  agriculture  come  to 
maturity,  we  are  led  to  conclusions  which  are  not  without  interest. 
A  knowledge  of  the  mean  temperature  of  a  place  situated  between 
the  tropics  suffices  of  itself  to  give  us  an  idea  of  the  nature  of  its 
agriculture  ;  in  fact,  the  temperature  of  each  day  differs  little  from 
that  of  the  entire  year,  during  which  vegetable  life  proceeds  without 
interruption.  It  is  altogether  different  with  regard  to  countries  sit 
uated  beyond  the  limits  of  the  torrid  zone.  The  mean  annual  tem- 
perature is  not  then  a  datum  sufficient  to  enable  us  to  appreciate  the 
agricultural  importance  of  a  country.  In  order  to  know  what  the 
earth  will  produce,  the  temperature  proper  to  the  different  seasons 
of  the  year  must  be  known  ;  in  a  word,  it  is  the  mean  temperature 
of  the  cycle  in  which  vegetation  begins  and  ends  that  it  imports  us 
to  ascertain,  in  order  to  learn  what  the  useful  plants  are  which  may 
be  required  of  the  soil. 

In  examining  the  question  which  now  engages  us,  we  first  inquire 
what  time  elapses  between  the  sprouting  of  a  plant  and  its  maturity 

♦  Humboldt's  Central  Asia,  vol.  Ul.  p.  49. 

41 


482  METEOROLOGY. GROWTH  OF  PLANTS. 

end  then  we  determine  the  temperature  of  the  interval  which  sepe 
rates  these  two  extreme  epochs  in  vegetable  life.  In  comparing 
these  data  with  reference  to  the  same  species  of  plant  grown  in  Eu 
rope  an  1  America,  we  arrive  at  the  following  curious  result,  that  the 
number  of  days  that  elapse  between  the  commencement  of  vegeta 
tion  and  the  period  of  ripeness,  is  by  so  much  the  greater  as  the 
mean  temperature  is  lower.  The  duration  of  the  life  of  the  vegeta- 
ble would  be  the  same,  however  different  the  climate,  were  this  tem- 
perature identical ;  it  will  be  longer  or  it  will  be  shorter  as  the  mean 
temperature  of  the  cycle  itself  is  lower  or  higher.  In  other  words, 
the  duration  of  the  vegetation  appears  to  be  in  the  inverse  ratio  of 
the  mean  temperature ;  so  that  if  we  multiply  the  number  of  days 
during  which  a  given  plant  grows  in  different  climates,  by  the  mean 
temperature  of  each,  we  obtain  numbers  that  are  very  nearly  equa' 
This  result  is  not  only  remarkable  in  so  far  as  it  seems  to  indicate 
that  upon  every  parallel  of  latitude,  at  all  elevations  above  the  level 
of  the  sea,  the  same  plant  receives  in  the  course  of  its  existence  an 
equal  quantity  of  heat,  but  it  may  find  its  direct  application  by  ena- 
bling us  to  foresee  the  possibility  of  acclimating  a  vegetable  in  a 
country,  the  mean  temperature  of  the  several  months  of  which  is 
known. 

CULTIVATION  OF  WHEAT,  ALSACE. 

In  1835  we  sowed  our  wheat  on  the  1st  of  November ;  the  cold 
set  in  shortly  after  the  plant  had  sprung,  and  the  harvest  took  place 
the  16th  of  July,  1836.  The  vegetation  during  the  last  days  of  au- 
tumn is  so  sl6w  and  irregular,  that  it  may  be  assumed  without  sensi- 
ble error,  that  it  really  begins  in  spring,  when  the  frosts  are  no  longer 
felt ;  from  this  period  only  does  it  proceed  without  interruption.  For 
Alsace  I  regard  this  period  as  beginning  with  the  1st  of  March. 

The  period  of  the  growth  was,  therefore,  137  days,  the  mean  tem- 
perature was  59°  F.,  (3083°  F.) 

Tremois  wheat,  this  same  year,  required  131^days  to  ripen  under 
a  mean  temperature  of  between  60°  and  61°  F.,  (7925°  F.) 

At  Paris,  setting  out  from  the  31st  of  March,  wheat  generally  re- 
quires 160  days  to  attain  maturity,  the  mean  temperature  being 
about  56°  F.,  (8960°  F.) 

At  Alais  the  month  of  February  having  generally  but  few  days 
of  heat,  it  may  be  regarded  as  the  epoch  when  the  continued  vege- 
tation of  autumn-sown  wheat  commences.  The  harvest  taking 
place  on  the  27th  of  June,  the  number  of  days  whic  h  it  requires  to 
ripen  is  146,  the  mean  temperature  being  between  57°  and  68°  F. 
(8322°  F.) 

CULTIYATION  OF  WHEAT  IN  AMERICA. 

At  Kingston,  New  York,  the  wheat  is  sown  in  autumn  ;  Tegeta- 
tion  suspended  through  the  winter  resumes  its  activity  in  the  begin- 
ning of  April,  and  the  harvest  takes  place  about  the  1st  of  August 
The  crop  is  therefore  growing  during  about  122  days  under  the  in- 
fluence of  a  mean  temperature  of  63°  F.  (7680°  F.) 


METEOROLOGY. GROWTH  OF  PLANTS.  488 

In  the  same  place  Tremois  wheat  is  sown  in  the  beginning  of 
May,  and  the  harvest  takes  place  towards  the  15th  of  August,  so 
that  it  is  106  days  on  the  ground  under  a  mean  temperature  of  68°  F  . 
(7208°  F.) 

At  Cincinnati  the  wheat  sown  in  the  end  of  February  is  harvest- 
ed in  the  2d  week  in  July,  say  the  15th  day,  the  crop  is  therefore 
137  days  on  the  ground  under  a  mean  temperature  of  between  60°  and 
61°  F.  (8288°  F.) 

INTERTROPICAL    REGION. 

Wheat  sown  at  the  end  of  February  was  reaped  on  the  25th  of 
July  at  Zimijaca,  plain  of  Bogota,  having  been  147  days  on  the 
ground,  the  mean  temperature  being  between  58°  and  59°  F. 
(8526°  F.) 

At  Quinchuqui  the  vegetation  of  wheat  begins  in  February  and 
ends  in  the  month  of  July,  say,  181  days;  and  I  found  the  mean 
temperature  to  be  between  57°  and  58°  F. 

At  Venezuela,  according  to  M.  Codazzi,  wheat  to  ripen  require? 
92  days  at  Turmero,  mean  temperature  between  75.2°  and  76°  F., 
(6918°  F. ;)  100  days  at  Truxillo,  mean  temperature  72.1"  F., 
(7210°  F.) 

CULTIVATION  OP  BARLEY. 

Of  the  cereals,  barley  is  that  which  succeeds  in  the  most  diversi- 
fied climates.  It  comes  to  maturity  under  the  burning  heats  of  the 
tropics ;  and  in  regions  where  the  mean  and  constant  temperature 
is  scarcely  52°  F.,  fields  of  barley  of  great  beauty  are  still  en- 
countered. 

At  Alsace  (Bechelbronn)  barley  sown  at  the  end  of  April  was 
harvested  on  the  1st  of  August.  It  had  remained  92  days  on  the 
ground,  the  mean  temperature  having  been  between  66°  and  67°  F., 
(6118°  F.) 

Winter  barley  sown  on  the  1st  of  November  was  cut  on  the  1st 
of  July.  Reckoning  the  period  of  active  vegetation  from  the  1st 
of  March,  it  was  122  days  in  coming  to  maturity,  the  mean  temper- 
ature having  been  between  58°  and  59°  F.,  (7076°  F.) 

At  Alais  winter  barley  is  harvested  on  the  18th  of  June.  As- 
suming that,  as  in  the  case  of  wheat,  the  1st  of  February  is  the  date 
of  commencing  vegetation,  it  must  have  taken  137  days  to  come  to 
maturity  under  a  mean  temperature  between  55°  and  56°  F. 

In  Egypt  upon  the  banks  of  the  Nile  barley  is  sown  in  the  end 
of  November,  and  the  harvest  takes  place  at  the  end  of  February, 
at  an  interval  therefore  of  90  days,  and  the  mean  temperature  of  the 
winter  at  Cairo  is  nearly  70°  F.,  (6300°  F.) 

At  Kingston,  North  America,  the  barley  is  sown  in  the  begin- 
ning of  May,  and  the  crop  is  cut  towards  the  beginning  of  August, 
in  about  92  days,  therefore,  the  mean  temperature  being  between 
66°  to  67"  F. 

At  Cumbal  under  the  line  there  is  no  fixed  period  for  sowing 
bailey.     It  is  generally  put  into  the  ground  on  the  approach  of  th« 


i64  METEOROLOGY. GROWTH  OF  PLANTS. 

rain}'  season  about  the  1st  of  June,  and  it  is  then  reaped  about  the 
middle  of  November  ;  it  therefore  stands  on  the  ground  for  about 
168  days,  and  the  mean  temperature  is  between  51°  and  52°  F. 

At  Santa  Fe  de  Bogota  they  reckon  about  four  months  between 
the  barley  seed-time  and  harvest,  or  about  122  days,  the  mean  tem- 
perature being  between  58°  and  59°  F. 

CITLTIVATION  OF  MAIZE,  OR  INDIAN  CORN. 

In  the  neighborhood  of  Bechelbronn  the  maize  which  sprouted  on 
the  first  of  June  yielded  an  abundant  harvest  on  the  1st  of  October) 
the  mean  temperature  having  been  68°  F. 

In  South  America  maize  comes  to  maturity  in  the  course  of  three 
months,  say  92  days,  the  mean  temperature  being  between  81°  and 
82°  F.;  but  on  the  elevated  plains,  as  that  of  Santa  Fe,  maize  will 
require  six  months  to  come  to  maturity,  say  183  days,  and  there  the 
mean  temperature  is  69"  F. 

CULTIVATION  OF  THE  POTATO. 

In  1836  our  potatoes  at  Bechelbronn  were  put  into  the  ground  on 
the  1st  of  May,  and  the  crop  was  gathered  on  the  15th  of  October, 
after  157  days,  therefore,  the  mean  temperature  having  been  about 
65°  F.;  but  in  ordinary  years,  when  the  temperature  is  less  elevated 
than  that  of  1836,  the  potato  crop  is  generally  gathered  at  the  end 
of  October,  after  183  days,  the  mean  temperature  having  been  as 
before  nearly  59°  F. 

In  the  neighborhood  of  Alais  potatoes  are  planted  at  the  end  of 
March  and  taken  up  about  the  1st  of  September,  after  five  months 
or  153  days,  the  mean  temperature  of  which  has  been  70°  F. 

According  to  M.  Codazzi  potatoes  are  grown  near  the  lake  of  Va- 
lencia, (Venezuela,)  in  120  days,  and  the  mean  temperature  of  Ma- 
racaibo  near  the  lake  is  78°  F. 

According  to  the  same  observer,  the  potato  still  yields  good  crops 
at  Merida  in  the  Cordilleras,  where  the  mean  temperature  is  between 
71°  and  72°  F.,  and  the  growth  lasts  about  4^  months. 

On  the  temperate  levels  of  New  Granada  at  Santa  F6  I  saw  po- 
tatoes set  in  the  middle  of  December  immediately  after  the  rainy 
season,  and  the  harvest  was  gathered  in  the  course  of  the  first  week 
in  June,  the  crop  therefore  was  at  least  200  days  in  the  ground,  the 
mean  temperature  having  been  between  58°  and  59°  F. 

On  the  occasion  of  my  ascent  of  the  volcanic  mountain,  Antisana, 
I  ate  on  the  4th  of  August  some  potatoes  which  had  just  been  gath- 
ered, and  which  had  been  planted  in  the  beginning  of  November,  so 
that  the  crop  had  been  276  days  in  the  ground,  the  mean  tempera- 
ture of  the  country  being  52°  Fahr. 

But  this  is  not  yet  the  superior  limit  to  the  cultivation  of  potatoes 
under  the  equator.     They  are  still  grown  at  Cambugan,  the  mear 
temperature  of  which  scarcely  exceeds  49°  Fahr.,  the  plant  remain 
ing  nearly  eleven  months  in  the  ground,  and  the  crop  being  frequentlj 


METEOROLOGY. GROWTH  OF  PLANTS.  48ft 

lo«<  from  frorta  that  occur  at  this  great  elevation  in  the  course  of 
the  mouths  of  November  and  January. 

CULTIVATION  OF  THE  INDIGO  PLANT. 

In  "Venezuela,  in  plantations  very  near  the  level  of  the  sea,  the 
first  crop  is  cut  about  eighty  days  after  sowing.  The  mean  tem- 
perature is  there  between  81°  and  82°  Fahr.  In  other  countries 
where  the  mean  temperature  ranges  between  72°  and  74°  Fahr., 
which  must  be  regarded  as  the  limits  to  the  growth  of  indigo,  the 
first  cutting  takes  place  3^  months  or  106  days  after  the  sowing. 
In  India  the  first  cutting  seems  generally  to  occur  about  ninety  days 
after  the  sowing,  and  the  mean  temperature  of  the  two  winter  months 
and  of  the  summer  months  wheii  the  crop  is  on  the  ground,  at  Bom- 
bay is  about  76°  Fahr. 

I  shall  terminate  this  section  by  calling  the  attention  of  vegetable 
physiologists  to  a  fact  which  appears  to  have  escaped  them.  It  is 
this  :  that  plants  in  general,  those  of  tropical  countries  very  obvi- 
ously so,  spring  up,  live,  and  flourish  in  temperatures  that  are  nearly 
the  same.  In  Europe  and  in  North  America,  an  annual  plant  is 
subjected  to  climatic  influences  of  the  greatest  diversity.  The 
cereals,  for  example,  germinate  at  from  43°  to  47°  or  48° ;  they  get 
through  the  winter  alive,  making  no  progress ;  but  in  the  spring 
they  shoot  up,  and  the  ear  attains  maturity  at  a  season  when  the 
temperature,  which  has  risen  gradually,  is  somewhat  steady  at  from 
74°  to  78°  Fahr. 

In  equinoctial  countries  Aings  pass  diflferently :  the  germination, 
growth,  and  ripening  of  grain  take  place  under  degrees  of  heat  which 
are  nearly  invariable.  At  Santa  Fe  the  thermometer  indicates 
79°  Fahr.  at  seed  as  at  harvest  time.  In  Europe  the  potato  is 
planted  with  the  thermometer  at  from  50°  to  54°  Fahr.,  and  it  does 
not  ripen  until  it  has  had  the  heats  of  July  and  August.  But  we 
have  just  seen  that  this  plant  grows,  slowly  indeed,  but  regularly,  in 
places  where  the  temperature,  nearly  invariable,  does  not  rise  above 
48.2°  or  50°  Fahr. 

Germination,  and  the  evolution  of  those  organs  by  which  vegeta- 
bles perform  their  functions  in  the  soil  and  in  the  air,  take  place  at 
temperatures  that  vary  between  32°  and  112°  Fahr.;  but  the  most 
important  epoch  in  their  life,  ripening,  generally  happens  within 
much  smaller  limits,  and  which  indicate  the  climate  best  adapted  to 
their  cultivation,  if  not  always  to  their  growth  ;  for  the  vine  grows 
lustily  in  many  places  where  its  fruit  never  ripens.  To  produce 
drinkable  wine,  a  vineyard  must  have  not  only  a  summer  and  an 
autumn  sufficiently  hot ;  it  is  indjspensable  in  addition  that  at  a  given 
period — that,  namely,  which  follows  the  appearance  of  the  seeds — 
there  be  a  month,  the  mean  temperature  of  which  does  not  fall  below 
19°  cent,  or  about  66|°  Fahr.,  a  fact  of  which  conviction  may  be 
obtained  from  the  following  table  which  1  borrow  from  M.  de  Huitt- 
boldt: 

41* 


im 


METEOROLOGY. — GROWTH  OF  PLANTS. 


Temperature  of  Temperature 

summer.  w  autumn. 

Bordeaux 70®  Fahiu  58" 

Frankfort,  A.  M- .     65  50 

Lausanne 65.2  49.7 

Paris 65.8  52.2 

Berlin 63.2  48.0 

London 62.9  51.3 

Cherbourg 61.9  54.4 


Temperature  of 
the  hottest  month 

73.3®  F.  very  favorahl* 

66.0 

65.8 

66.2 

64.4  Wine  scarcely  drinkable 

64.1  Vice  not  cultivated. 

63.2 


In  high  latitudes  the  disappearance  of  vigorous  vegetation  in  plants 
day  depend  quite  as  much  on  intensity  of  winter  colds  as  on  insuf- 
ficiency of  summer  heat.  The  equable  climate  of  the  equatorial  re- 
gions is  therefore  much  better  adapted  than  that  of  Europe  to  de- 
termine the  extreme  limits  of  temperature  between  which  vegetable 
species  of  different  kinds  will  attain  to  maturity.  Thus  it  has  been 
found  that  the  vine  between  the  tropics  is  productive  in  temperatures 
that  vary  from  69°  F.  to  79°  or  80°.  I  shall  terminate  with  a  list  of 
the  temperatures  favorable  to  the  particular  vegetables  in  the  success 
of  which  man  is  more  especially  interested. 


^«Ttimiim.   Miuimtuit. 

Pine-apple " 

Melon " 

Vanilla  " 

Guaduas " 

The  vine 79 

CotBse 79 

Anise 77 

Wheat 74(1) 

Barley 74         59 

Potatoes   75(1)  52 

Arachaca 75         49 

Flax 74         54 

Apple 72         59 

Oak 67         61 


Maximum.    Minimum. 
The  cocoa,  or  chocolate  bean  82®  F.    73°  F. 

Banana "  64 

Indigo   "  71 

Sugar-cane "  71 

Cocoa-nut "  78 

Palm "  78 

Tobacco "  65 

Manihot "  72 

Cotton-tree "  67 

Maize "  50 

Haricots "  59 

OrchU "  72 

Rice "  75 

Calabash "  72 

rjaricapapaya "  66 

^  IV.    COOLING  THROUGH  THE  NIGHT ;    DEW,  RAIN. 

When  the  sky  is  clear  and  calm  during  the  night,  vegetables  cooi 
down  and  very  soon  show  a  temperature  inferior  to  that  of  the  air 
which  surrounds  them.  This  property  of  cooling  in  such  circum- 
stances belongs  to  all  bodies  ;  but  all  do  not  possess  it  to  the  same 
degree.  Organic  substances,  for  instance,  such  as  wool  or  cotton, 
feathers,  &c.,  radiate  powerfully  and  sink  low  ;  polished  metals,  on 
the  contrary,  have  a  very  weak  emissive  or  radiating  power ;  and 
air  and  the  gases  in  general  radiate  still  more  feebly. 

Inasmuch  as  a  body  is  continually  emitting  heat,  its  temperature 
can  only  remain  stationary  so  long  as  it  receives  from  surrounding 
objects  at  every  instant  a  quantity  of  caloric  precisely  equal  in  quan- 
tity to  that  which  it  loses  from  its  surface. 

From  the  moment  that  these  incessant  exchanges  cease  to  be  i: 
a  state  of  perfect  equality,  the  temperature  of  a  body  varies ;  it  may 
even  experience  a  considerable  degree  of  cooling  if  it  is  exposed 
during  a  clear  night  in  an  open  spot.  In  such  circumstances,  a  body 
gives  off  towards  all  the  visible  parts  of  the  heavens  more  heat  than 
P  wceives ;  for  the  higher  regions  of  the  atmosphere  are  excessive* 


METEOROLOGY. NIGHT  COOLING.  487 

ly  cold,  a  fact  which  is  proved  by  the  rapid  diminution  of  tempera- 
ture experienced  on  ascending  mountains,  or  by  rising  into  the  air 
in  balloons.  The  internal  temperature  of  the  globe,  the  tendency 
of  which  would  be  to  compensate  the  loss  experienced  by  the  body 
which  radiates,  has  scarcely  any  effect  in  lessening  the  cooling,  be- 
cause it  is  propagated  with  extreme  slowness,  in  consequence  of  the 
indifferent  conducting  powers  of  the  earthy  substances  of  which  its 
crust  is  composed.  The  air,  lastly,  which  surrounds  the  radiating 
body,  does  not  warm  it  save  in  the  most  minute,  inappreciable  degree, 
and  rather  by  its  contact  than  by  transmitting  to  it  rays  of  heat,  for 
the  gases  have  only  very  limited  emissive  powers.  It  is  even  in 
consequence  of  the  small  amount  of  this  power  that  the  stratum  of 
air  in  contact  with  the  surface  of  the  ground,  does  not  by  any  means 
sink  in  the  same  proportion  as  the  surface  upon  which  it  lies.  Thus, 
in  the  circumstances  which  I  have  indicated,  a  thermometer  laid 
upon  the  ground  always  indicates  a  temperature  lower  than  that 
which  is  proclaimed  by  one  suspended  in  the  air ;  and  the  difference 
is  by  so  much  the  greater  as  the  radiating  power  of  the  bodies  ex- 
posed is  more  decided,  or  as  it  may  take  place  into  a  greater  extent 
of  the  heavens.  Every  cause  which  agitates  the  air,  which  disturbs 
its  transparency,  which  contracts  the  extent  of  the  visible  sphere, 
interferes  with  nocturnal  radiation,  and  therefore  with  cooling.  A 
cloud,  like  a  screen,  compensates  either  in  whole  or  in  part  accord- 
ing to  its  proper  temperature,  for  the  loss  of  heat  which  a  body  upon 
the  surface  of  the  earth  experiences  in  radiating  into  space.  Wind, 
by  continually  renewing  the  air  which  is  in  contact  with  the  surface 
of  bodies  tending  to  cool  by  radiation,  always  diminishes  its  effect  to 
a  certain  extent.  It  is  for  this  reason  that  a  cloudless  sky  and  a 
calm  atmosphere,  when  nocturnal  radiation  attains  its  maximum,  are 
most  dangerous  or  injurious  to  our  harvests. 

In  a  night  which  combines  all  the  conditions  favorable  to  radiation, 
a  thermometer  of  small  size  laid  upon  the  grass  will  be  found  to 
mark  from  10°  to  14°  or  15°  Fahr.  below  the  temperature  of  the  sur- 
rounding atmosphere.  Thus  in  the  temperate  zone  in  Europe,  as 
Mr.  Daniell  has  observed,  the  temperature  of  meadows  and  heaths 
is  liable  to  fall  during  ten  months  of  the  year  by  the  mere  effect  of 
nocturnal  radiation  to  a  temperature  below  the  freezing  point  of 
water ;  this  is  particularly  apt  to  happen  both  in  spring  and  autumn, 
when  the  destructive  effects  of  radiation  are  most  to  be  apprehend- 
ed, the  nocturnal  radiations  of  those  seasons  frequently  lowering  the 
temperature  several  degrees  below  the  freezing  point. 

A  few  observations  which  I  made  upon  nocturnal  radiation  at  dif- 
ferent heights  in  the  Cordilleras,  seem  to  indicate  that  its  effects 
there  are  less  decided  than  in  Europe,  in  consequence  perhaps  of 
the  greater  quantity  of  heat  acquired  by  the  ground  in  the  course  of 
the  day.  It  appears  that  in  this  mountain  range  it  rarely  freezes  at 
a  height  less  than  6560  feet  above  the  level  of  the  sea  ;  although 
.here  are  certain  circumstances  there  which  favor  nocturnal  radia- 
tion so  much,  that  it  is  really  impossible  to  indicate  any  very  precise 
timits.     In  a  general  way  it  may  be  said  that  the  crops  of  thosr 


488  meteorol:>gy. — night  cooling. 

plains  which  are  sufficiently  elevated  to  hare  a  mean  temperature 
of  from  50°  to  58°  Fahr.  are  exposed  to  suffer  from  frost ;  it  fre- 
auently  happens  that  a  crop  of  wheat,  barley,  maize,  or  potatoes,  of 
the  richest  appearance,  is  destroyed  in  a  single  night  by  the  effect 
of  radiation.  In  Europe  during  the  fine  nights  of  April  and  May, 
when  the  air  is  calm  and  the  sky  clear,  buds,  leaves,  and  young 
shoots  are  frequently  cut  off,  are  frozen  ;  in  a  word,  although  a  ther- 
mometer in  the  air  indicates  several  degrees  above  the  point  of  con- 
gelation. Market  gardeners  and  others  who  are  much  exposed  to 
loss  from  this  cause,  ascribe  the  effect  to  the  light  of  the  mc  in  of  the 
months  of  April  and  May  ;  and  they  ground  their  opinion  upon  the 
fact  that  when  the  sky  is  clouded,  the  destructive  effects  of  frost  are 
not  apparent,  although  the  same  temperature  of  the  atmosphere  be 
indicated  by  the  thermometer. 

In  the  lower  ranges  of  the  Cordilleras,  farmers  also  ascribe  the 
same  injurious  consequences  to  the  light  of  the  moon,  wuth  this  dif- 
ference, that  according  to  them  the  destructive  influence  continues 
throughout  the  year ;  and  it  is  not  unworthy  of  remark  that,  in  the 
neighborhoods  of  Paris  and  of  London,  the  mean  temperature  of  the 
months  of  April  and  May  (from  50°  to  57°,  or  58°  F.)  represents  ex- 
actly the  invariable  climate  of  those  places  among  the  Andes,  where 
the  effects  of  frost  upon  vegetation  are  particularly  to  be  apprehend- 
ed. M.  Arago  has  shown,  that  the  cold  ascribed  to  the  light  of  the 
moon  is  nothing  but  a  consequence  of  the  nocturnal  radiation,  at  a 
season  when  the  thermometer  in  the  air  is  frequently  at  from  40°  to 
43°  F.  and  the  sky  is  clear  and  calm.  At  this  temperature  a  plant, 
radiating  into  space,  readily  falls  below  the  point  of  congelation, 
and  then  the  hopes  of  the  gardener  and  farmer  are  destroyed.  The 
phenomenon  takes  place  particularly  in  a  bright  night :  and  if  the 
moon  happen  to  be  up  when  it  occurs,  the  influence  is  ascribed  by 
the  vulgar  to  her  light.  Were  the  sky  clouded,  the  principal  con- 
dition to  radiation  would  be  wanting  ;  the  temperature  of  objects  on 
the  surface  of  the  ground  would  not  fall  below  that  of  the  surround- 
ing medium,  and  plants  would  not  freeze  unless  the  air  itself  fell  to 
32°  F. 

The  observation  of  gardeners,  therefore,  as  M.  Arago  remarks, 
was  not  in  itself  false,  it  was  only  incomplete.  If  the  freezing  of 
the  soft  and  delicate  parts  of  vegetables  in  circumstances  when  the 
air  is  several  degrees  above  the  freezing  point,  be  really  due  to  the 
escape  of  caloric  into  planetary  space,  it  must  happen  that  a  screen 
placed  above  a  radiating  body,  so  as  to  mask  a  portion  of  the  heav- 
ens, will  either  prevent  or  at  least  diminish  the  amount  of  the  cooling. 
And  that  this  takes  place  in  fact,  appears  from  the  beautiful  experi- 
ments of  Dr.  Wells.  A  thermometer,  placed  upon  a  plank  of  a 
certain  thickness,  and  raised  about  a  yard  above  the  ground,  oc- 
casionally indicates  in  clear  and  calm  weather  from  6°  to  T  or  8°  F. 
ess  than  a  second  thermometer  attached  to  the  lower  surface  of 
he  plank.  It  is  in  this  way  that  we  explain  the  use  of  mats,  of 
ayers  of  straw,  in  a  word,  of  all  those  slight  coverings  which  gar- 
deners are  so  careful  to  supply  during  the  night  to  delicate  plamts  ai 


METEOROLOGY. NIGHT  FROSTS.  489 

eertain  seasons  of  the  year.  Before  men  were  aware  that  bodies  on 
the  surface  of  the  ground  became  colder  than  the  air  which  sur- 
rounds them  during  a  clear  night,  the  rationale  of  this  practice  was  not 
apparent ;  for  it  was  altogether  impossible  to  conceive  that  coverings 
8o  slight  could  protect  vegetables  from  a  low  temperature  of  the  air. 

The  means  indicated,  as  simple  as  they  are  effectual  in  protecting 
plants  in  the  garden,  are  rarely  applicable  in  farming,  where  the 
surface  to  be  preserved  is  always  very  extensive.  Nevertheless,  in 
severe  winters,  the  frost  by  penetrating  the  ground  would  frequently 
destroy  the  fields  sown  in  autumn,  were  it  not  that  in  high  latitudes 
the  snow  which  covers  the  surface  becomes  a  powerful  obstacle  to 
excessive  cooling,  by  acting  at  one  and  the  same  time  as  a  covering, 
and  as  a  screen  preventing  radiation.  As  a  covering,  because  snow 
is  one  of  the  worst  of  conductors,  one  of  those  substances  which  for  a 
given  thickness  opposes  the  passage  of  heat  most  effectually  ;  it  is, 
therefore,  an  obstacle  almost  insurmountable  to  the  earth  beneath  it 
getting  into  equilibrium  in  point  of  temperature  with  the  atmosphere. 
As  a  screen,  because  in  sheltering  the  ground  it  prevents  it  from 
undergoing  the  cooling  which  it  would  not  fail  to  experience  in  clear 
nights  by  radiation  into  the  open  firmament.  It  is  familiarly  known 
in  many  parts  of  Europe,  that  the  accidental  want  of  the  usual  cov- 
ering of  snow  will  cause  the  loss  of  the  autumn-sown  crops  of  grain 
It  is  on  the  surface  of  the  snow  that  the  great  depression  of  temper- 
ature takes  place ;  and  the  substance  being  a  very  bad  conductor, 
the  earth  cools  in  a  much  less  degree.  In  the  month  of  February, 
1841,  I  made  some  experiments,  which  show  that  the  snow  which 
covers  the  ground  acts  in  the  manner  of  a  screen.  I  had  first  a 
thermometer  upon  the  snow,  the  bulb  of  the  instrument  being  cover- 
ed by  from  0.078  to  0.117  of  an  inch  of  snow  in  powder  ;  second,  a 
thermometer,  the  bulb  of  which  was  situated  completely  under  the 
layer  of  snow  in  contact  with  the  ground ;  third,  a  thermometer 
in  the  open  air,  at  about  37  or  38  feet  above  the  surface,  on  the  north 
of  a  building.  The  layer  of  snow  was  about  four  inches  in  thickness, 
an  J  had  covered  a  field  sown  with  wheat  for  a  month.  The  sun 
shone  brightly  upon  the  field  on  those  days  when  my  experiments 
were  made. 

Feb.  11.  Five  o'clock  in  the  evening;  the  sun  has  been  hidden 
by  the  mountains  for  half  an  hour ;  the  sky  is  unclouded,  the  air  very 
calm  :  thermometer  under  the  snow,  32'  F.  ;  thermometer  upon  the 
snow,  29°  F. ;  thermometer  in  the  air,  36.3'  F. 

Feb.  12.  The  night  very  fine,  no  clouds,  the  air  calm.  At  sevea 
o'clock  in  the  morning,  the  sun  is  not  yet  upon  the  field  :  thermom 
eter  under  the  snow,  26.2"  F.  ;  thermometer  upon  the  snow,  10"  F. ; 
thermometer  in  the  air,  26.3°  F. 

At  half-past  five  in  the  evening,  the  sun  behind  the  mountains : 
thermometer  under  the  snow,  32°  F.  ;  thermometer  upon  the  snow, 
29°  F. ;  thermometer  in  the  air,  37.5°  F. 

Feb.  13.  At  seven  in  the  morning ;  the  sky  gray,  the  air  slightly 
in  motion :  thermometer  under  the  snow,  28°  F.  ;  thermometer 
upon  the  snow,  17°  F. ;  thermometer  in  the  air,  25°  F. 


too  METEOROLOGY. DEW. 

At  half-past  five  in  the  evening ;  the  air  calm,  the  sky  cloudlesSj 
the  sun  already  concealed  for  some  time :  thermometer  under  the 
snow,  32°  F.  ;  thermometer  upon  the  snow,  30°  F.  ;  thermometer 
in  the  air,  40°  F. 

Feb.  14.  Seven  in  the  morning,  wind  W.,  a  fine  rain  falling: 
thermometer  under  the  snow,  32°  F. ;  thermometer  upon  the  snow. 
32°  F.  ;  thermometer  in  the  air,  35.7°  F. 

When  we  reflect  upon  the  losses  occasioned  to  farmers  and  mar- 
ket gardeners  by  frosts  that  are  entirely  due  to  nocturnal  radiation 
?t  seasons  of  the  year  when  vegetation  has  already  made  considera- 
ble progress,  we  ask  eagerly  if  there  be  no  possible  means  of  guard- 
ing against  them.  I  shall  here  make  known  a  method  imagined  and 
successfully  followed  by  South  American  agriculturists  with  this 
view.  The  natives  of  the  upper  country  in  Peru  who  inhabit  the 
elevated  plains  of  Cusco  are  perhaps  more  than  any  other  people 
accustomed  to  see  their  harvest  destroyed  by  the  effects  of  nocturnal 
radiation.  The  Incas  appear  to  have  ascertained  the  conditions 
under  which  frost  during  the  night  was  most  to  be  apprehended. 
They  had  observed  that  it  only  froze  when  the  night  was  clear  and 
the  air  calm :  knowing  consequently  that  the  presence  of  clouds 
prevented  frost,  they  contrived  to  make  as  it  were  artificial  clouds 
to  preserve  their  fields  against  the  cold.  When  the  evening  led 
them  to  apprehend  a  frost — that  is  to  say,  when  the  stars  shone  with 
brilUancy,  and  the  air  was  still — the  Indians  set  fire  to  a  heap  of  wet 
straw  or  dung,  and  by  this  means  raised  a  cloud  of  smoke,  and  so 
destroyed  the  transparency  of  the  atmosphere  from  which  they  had 
so  much  to  apprehend.  It  is  easy  in  fact  to  conceive  that  the 
transparency  of  the  air  can  readily  be  destroyed  by  raising  a  smoke 
in  calm  weather  ;  it  would  be  otherwise  were  there  any  wind  stir- 
ring ;  but  then  the  precaution  itself  becomes  unnecessary,  for  with 
air  in  motion,  with  a  breeze  blowing,  there  is  no  reason  to  apprehend 
frost  from  nocturnal  radiation. 

The  practice  followed  by  the  Indians  just  described  is  mentioned 
by  the  Inca  Garcillaso  de  la  Vega  in  his  Royal  Commentaries  of 
Peru.  Garcillaso  in  the  imperial  city  of  Cusca,  and  in  his  youth, 
had  frequently  seen  the  Indians  raise  a  smoke  to  preserve  the  fields 
of  maize  from  the  frost.* 

The  cooling  of  bodies  occasioned  by  nocturnal  radiation  is  always 
accompanied  by  a  deposite  of  moisture  upon  their  surface  under  the 
form  of  minute  globules  :  this  is  dew.  The  ingenious  experiments 
of  Wells  having  demonstrated  that  the  appearance  of  dew  always 
follows,  never  precedes  the  fall  in  temperature  of  the  bodies  on 
•vhich  it  is  deposited,  the  phenomenon  cannot  be  attributed  to  any 
hing  more  than  a  simple  condensation  of  the  watery  vapor  con- 
ained  in  the  air,  comparable  in  all  respects  to  that  which  takes 
■)lace  upon  the  surface  of  a  vessel  containing  a  fluid  that  is  colder 
han  t'le  air.f     The  quantity  of  moisture  dissolved  in  the  atmosphere 

*  The  good  effects  of  smoke  in  preventing  nocturnal  congelation  are  also  sigLalued 
oy  Pliny  the  naturalist, 
t  Aiigo,  Annusiire  des  Longitudes,  Aan*e  1837,  p.  160. 


METEOROLOGY. — DEW.  491 

is  by  so  much  tlie  greater  as  tlie  temperature  is  higher.  In  very 
warm  climates  the  dew  is  so  copious  as  to  assist  vegetation  essen- 
tially, supplying  the  place  of  rain  during  a  great  part  of  the  year. 

According  to  some  meteorologists  dew  is  most  copious  near  the 
sea-board  of  a  country  ;  very  little  falls  in  the  interior  of  great  con- 
tinents, and  indeed  is  said  only  to  be  apparent  in  the  vicinity  of  lakes 
and  rivers.*  I  cannot  agree  in  any  statement  of  this  kind  ipade  so 
absolutely.  I  have  never  had  occasion  to  see  more  copious  dews 
than  those  which  occasionally  fall  in  the  steppes  of  San  Martin  to 
the  east  of  the  eastern  Cordilleras,  and  at  a  very  great  distance 
from  the  sea ;  the  dew  was  so  copious  that  for  several  nights  I  found 
it  impossible  to  employ  an  artificial-horizon  of  black  glass  in  order 
to  take  the  meridian  altitude  of  the  stars ;  the  moment  the  apparatus 
was  exposed  there  was  such  a  quantity  of  water  deposited  on  the 
surface  that  it  soon  gathered  into  drops  and  trickled  off.  I  found  it 
necessary  to  have  recourse  to  mercury  to  reflect  the  star  under  ob- 
servation. During  the  clear  calm  nights  the  turf  of  these  immense 
plains  receives  a  considerable  quantity  of  moisture  in  the  form  of 
dew,  which  materially  assists  vegetation,  and  by  its  evaporation 
tempers  the  excessive  heat  of  the  ensuing  day.  In  tropical  coun- 
tries the  forests  contribute  to  keep  down  the  temperature.  In  very 
hot  countries  it  is  rare  to  be  out  in  a  cleared  spot,  when  the  night 
is  favorable  to  radiation,  without  hearing  drops  of  water,  produced 
by  the  copiousness  of  the  dew,  falling  continually  from  the  surround- 
ing trees,  so  that  forests  contribute  further  to  produce  and  to  main- 
tain springs  by  acting  as  condensers  of  the  watery  vapor  dissolved 
in  the  air.  I  might  cite  a  number  of  observations  upon  this  point 
which  I  made  in  the  forest  of  Cauca.  In  the  bivouac  between  the 
4th  and  5th  of  July,  1827,  the  night  was  magnificent ;  nevertheless, 
in  the  forest  which  began  at  the  distance  of  a  few  yards  from  our 
encampment,  it  rained  abundantly ;  by  the  light  of  the  unclouded 
moon  we  could  see  the  water  running  from  the  branches. 

It  is  possible  that  the  transpiration  from  the  green  parts  of  the 
trees  might  have  been  added  to  the  dew  condensed,  and  so  increased 
the  intensity  of  the  phenomenon  which  I  have  described  ;  but  I 
rather  incline  to  believe  that  the  cooling  of  the  leaves  by  way  of 
radiation  had  by  far  the  largest  share  in  the  production  of  this  dew- 
rain.  It  is  true  that  of  all  the  leaves  which  form  the  crown  of  a 
tree,  those  whose  surface  is  exposed  and  radiate  freely  into  space 
intercept,  as  would  a  screen,  the  radiation  of  the  leaves  and  branches 
which  are  not  so  exposed  ;  but,  as  M.  de  Humboldt  has  observed,  if 
the  leaves  and  branches  which  crown  a  tree  cool  directly  by  emis- 
sion, those  which  are  situated  immediately  beneath  them  by  radiating 
towards  the  lower  parts  of  the  leaves  which  are  already  cooled  a 
greater  quantity  of  heat  than  they  receive,  their  temperature  will 
also  necessarily  fall,  and  the  cooling  will  thus  be  propagated  from 
above  downward  until  the  whole  mass  of  the  tree  feels  its  effects 
It  is  thus  that  the  ambient  air  circulating  through  the  leaves  become* 

•  Kaemtz,  Meteorology,  translated  by  W.  Walker,  London-  1844. 


492  METEOROLOGY. — RAIN. 

cooled  during  bright  nights,  and  to  judge  from  the  influence  which 
forests  exert  in  lowering  the  temperature  of  a  country,  it  is  enough 
to  recollect  with  M.  de  Hunboldt  that  by  reason  of  the  vast  multi- 
plicity of  leaves,  a  tree,  the  crown  of  which  does  not  present  a  hori- 
zontal section  of  more  than  about  120  or  130  square  feet,  actually 
influences  the  cooling  of  the  atmosphere  by  an  extent  of  surface 
several  thousand  times  more  extensive  than  this  section. 

The  proportion  of  watery  vapor  which  a  gas  will  retain  in  solu- 
tion is  by  so  much  the  greater  as  the  tempe^rature  of  the  air  is 
higher.  All  the  causes  which  cool  air  saturated  with  watery  vapor 
occasion,  as  we  have  already  seen,  the  precipitation  of  a  certain 
quantity  of  moisture. 

When  this  condensation  takes  place  in  the  midst  of  a  gaseous 
mass,  the  precipitated  water  collects  into  small  floating  vesicles, 
which  trouble  the  transparency  of  the  medium  that  momentarily 
holds  them  in  suspension.  Mists,  fogs,  and  clouds  are  collections 
of  these  vesicles ;  a  fog,  as  a  celebrated  naturalist  said,  is  a  cloud 
in  which  one  is,  and  a  cloud  is  a  fog  in  which  one  is  not. 

The  vesicles  of  clouds  tend  towards  the  earth,  like  all  heavy  bo- 
dies, but  by  reason  of  their  specific  lightness  the  resistance  of  the 
air  which  they  displace  lessens  the  rapidity  of  their  descent.  When 
they  are  of  larger  size  they  coalesce  and  form  drops  of  water  which 
fall  with  greater  celerity.  When  these  drops  pass  through  strata 
of  very  dry  air  they  undergo  partial  evaporation,  and  this  is  the 
reason  wherefore  there  is  sometimes  less  rain  upon  plains  than  upon 
mountains.  In  opposite  circumstances  it  is  the  inverse  phenomenon 
that  is  observed  ;  the  drops  increase  in  size  in  passing  through  the 
inferior  strata  of  an  atmosphore  saturated  with  moisture,  condensing 
vapor  in  their  course.     This  is  what  happens  most  generally. 

In  taking  a  survey  of  a  large  amount  of  observations,  meteorolo- 
gists have  inferred  that  the  annual  quantity  of  rain  varies  with  the 
latitude  ;  that,  greatest  at  the  equator,  it  gradually  lessens  as  higher 
northern  and  southern  latitudes  are  attained ;  this  is  as  much  as 
saying  that  the  quantity  of  rain  is  greater  as  the  temperature  of  the 
climate  is  higher.  But  to  this  rule  there  are  numerous  exceptions ; 
for  instance,  under  the  line  at  Payta  on  the  sea-coast  it  only  rains 
very  rarely  ;  a  shower  of  rain  is  an  event,  and  when  I  visited  the 
country  eighteen  years  had  elapsed  since  they  had  had  any  thing  of 
a  fall  of  rain.  Local  causes  have  the  greatest  influence  upon  the 
fall  of  rain,  so  that  countries  on  the  same  parallel  of  latitude  are  far 
from  being  equally  distinguished  by  dryness  or  humidity. 

It  is  believed  that  in  Europe  it  rains  more  heavily  and  more  fre- 
quently in  the  day  than  in  the  night.  In  the  equinoctial  regions,  at 
least  in  those  parts  that  I  have  visited,  it  would  seem  that  the  op- 
posite rule  held  good.  Every  one  in  South  America  allows  that  it 
rains  principally  during  the  night,  and  the  observations  which  I 
made  in  the  neighborhood  of  Marmato  enable  me  to  state  that  of 
7.874  inches  of  rain  which  fell  in  the  month  of  October,  1.336  inches 
fell  in  the  day,  5.638  inches  in  the  night  ;  of  8.881  inches  which 
C?ll  in  the  month  of  November,  0.707  inches  came  dow;j  ir  the  day, 


METEOROLOGY. RAIN.  498 

8.174  inches  in  the  night ;  of  5.934  inches  which  fell  in  December, 
0.786  inches  fell  in  the  day,  5.148  inches  in  the  night. 

Two  series  of  observations  taken  in  the  same  country  al  two  sta- 
tions not  far  from  one  another,  but  situated  at  very  different  eleva- 
tions, seem  to  confirm,  in  reference  to  the  equatorial  regions,  the 
conclusions  of  European  meteorologists  as  to  the  fact  that  the  an- 
nual quantity  of  rain  which  falls  diminishes  as  the  height  above  the 
level  of  the  sea  increases.  They  also  show  that  in  latitudes  which 
do  not  differ  materially,  more  rain  falls  where  the  mean  temperature 
is  68°  F.  than  where  it  is  58°  F. 

Marmato  lies  in  N.  lat.  5°  27",  and  75°  11"  (1)  W.  long.,  at  a 
height  of  4676  feet  above  the  level  of  the  sea  ;  Santa  Fe  in  N.  lat. 
4°  36",  W.  long.  75°  6",  at  a  height  of  8692  feet  above  the  level  of 
the  sea.  And  while  the  quantity  of  rain  at  the  former  place  amount- 
ed, according  to  my  own  observations  for  1833,  to  60  inches,  ac- 
cording to  Caldas,  in  1807,  at  the  latter  there  fell  but  39.4  inches. 

In  temperate  climates  the  quantity  of  rain  that  falls  varies  with 
the  seasons.  Near  the  equator,  where  the  temperature  remains 
constant  throughout  the  year,  the  rainy  season  commences  precisely 
at  the  period  when  the  sun  approaches  the  zenith  ;  and  whenever  the 
latitude  of  a  place  in  the  torrid  zone  where  it  rains  is  of  the  same 
denomination  and  equal  to  the  declination  of  the  sun,  storms  occur. 
In  such  circumstances  the  sky  in  the  morning  is  of  remarkable  pu- 
rity, the  air  is  calm,  the  heat  of  the  sun  insupportable.  Towards 
noon  clouds  begin  to  show  themselves  upon  the  horizon,  the  hygrom- 
eter does  not  advance  towards  dryness  as  it  usually  does,  it  remains 
stationary,  or  even  falls  towards  extreme  humidity.  It  is  always 
after  the  sun  has  passed  the  meridian  that  the  thunder  is  heard, 
which  being  preceded  by  a  light  wind  is  soon  followed  by  a  deluge 
of  rain.  In  my  opinion  the  permanence  or  incessant  renovation  of 
storms  in  the  bosom  of  the  atmosphere  is  a  capital  fact,  and  is  con- 
nected with  one  of  the  most  important  questions  in  the  physics  of 
our  globe,  that  of  the  fixation  of  the  azote  of  the  air  by  organized 


The  most  recent  inquiries  show  dry  atmospherical  air  to  consist 

in  volume  of: 

Oxygen 20.8 

Azote....: 79.2 

The  air  contains  in  addition  from  2  to  5  10,000ths  of  carbonic  acid 
gas,  and  quantities  perhaps  still  smaller  of  carbureted  combustible 
gas.  The  experiments  of  M .  Theodore  de  Saussure,  as  well  as 
those  of  Professor  Liebig,  have  further  demonstrated  in  it  traces  of 
ammoniacal  vapor. 

I  have  already  shown  that  animals  do  not  directly  assimilate  the 
azote  of  the  atmosphere.  Azote  is  nevertheless  an  element  essen- 
tial to  the  constitution  of  every  living  being,  and  is  met  with  indif- 
ferently in  either  kingdom  of  nature.  If  we  inquire  into  the  sourc© 
5f  this  principle  in  connection  with  the  herbivorous  tribes  of  animals, 
we  find  it  as  an  element  in  the  food  which  sustains  them.  If  we 
next  inquire  into  the  immediate  origin  of  the  azote  which  entert 

42 


494  METEOROLOGY. RAIN. 

into  the  constitution  of  vegetables,  it  is  discovered  in  the  manure 
which  proceeds  more  >3pecially  from  animal  remains ;  for  vegeta- 
bles, to  thrive,  must  receive  azotized  aliment  by  their  roots.  We 
thus  come  to  apprehend  that  plants  supply  animals  with  their  azote, 
and  that  these  restore  it  to  plants  when  the  term  of  their  existence 
is  accomplished  ;  we  are  led  to  discover,  in  a  word,  that  living  or- 
ganic matter  derives  its  azote  from  dead  organic  matter. 

This  view  leads  us  to  conclude  that  the  amount  of  living  matter 
on  the  surface  of  the  globe  is  restricted  ;  that  its  limits  are  in  some 
sort  determined  by  the  quantity  of  azote  in  circulation  among  organ- 
ized beings ;  but  the  question  must  be  viewed  from  a  loftier  emi- 
nence, and  we  must  ask  what  is  the  origin  of  the  azote  which  enters 
into  the  constitution  of  organic  matter  considered  as  a  whole  1 

If  we  now  turn  to  the  possible  sources  or  magazines  of  azote,  we 
shall  find,  setting  aside  organized  beings  and  their  remains,  tnat 
there  is  in  truth  but  one,  the  atmosphere.  It  is  therefore  extremely 
probable  that  all  living  beings  have  previously  obtained  their  azote 
from  the  atmosphere,  just  as  it  seems  very  certain  that  they  have 
thence  derived  their  carbon.* 

The  most  reasonable  supposition  in  the  actual  state  of  science,  is 
to  consider  the  ammoniacal  vapors  diffused  through  the  atmosphere 
as  the  prime  source  of  the  azotized  principles  of  vegetables,  and 
then  through  them  of  animals ;  a  consequence  of  which  hypothesis 
would  be  to  assume  with  Liebig,  that  carbonate  of  ammonia  existed 
in  the  atmosphere  before  the  appearance  of  living  things  upon  the 
face  of  the  earth. 

The  phenomena  and  effects  of  thunder-storms  appear  to  me  cal- 
culated to  support  this  opinion.  It  is  known,  in  fact,  that  so  often 
as  a  succession  of  electrical  sparks  passes  through  moist  air,  there 
is  formation  and  combination  of  nitric  acid  and  ammonia.  Now  ni- 
trate of  ammonia  is  one  of  the  constant  ingredients  in  the  rain  of 
thunder-storms.  But  nitrate  of  ammonia,  being  a  fixed  salt,  cannot 
exist  in  the  atmosphere  in  the  state  of  gas  or  vapor ;  and  then  it  is 
not  the  nitrate,  but  the  carbonate  of  ammonia  that  has  been  signal- 
ized in  the  air.  In  bringing  to  mind  the  series  of  reactions  of  which 
I  have  spoken,  it  is  not  difficult  to  perceive  how  the  nitrate  of  am- 
monia, precipitated  in  thunder-showers,  and  thus  brought  into  contact 
with  calcareous  rocks,  should  suflfer  decomposition,  pass  into  the 
state  of  carbonate  on  the  return  of  fair  weather,  and  become  fitted 
to  undergo  diffusion  in  the  state  of  vapor  through  the  atmosphere. 
We  should  in  this  way  be  led  to  regard  the  electrical  agency,  the 
flash  of  lightning,  as  the  means  by  which  the  azote  of  the  atmosphere 
is  made  fit' for  assimilation  by  organized  beings.  In  Europe,  where 
thunder-storms  are  rare,  an  oflice  of  so  much  importance  will  per- 
haps be  accorded  reluctantly  to  the  electricity  of  the  clouds  ;  but  ia 
tropical  countries  no  difficulty  would  probably  be  felt  on  the  matter. 
In  the  torrid  zone,  thunder-storms  happen  in  one  place  or  another 
iSt  only  every  day,  but  every  hour,  and  even  every  minute  of  eTery 

*  Bonssingault,  Annales  de  Chimic,  t  Izxi  1838. 


METEOROLOGY. THUNDER-STORMS.  495 

hour  throughout  the  year ;  so  that  an  observer,  placed  at  th^j  equator, 
were  he  endowed  with  organs  of  sufficient  delicacy,  would  never 
lose  the  roll  of  the  thunder. 

As  the  equator  is  quitted,  the  times  at  which  rain  falls  become 
less  specific  or  periodical.  Under  the  tropics,  the  rains  of  thunder- 
storms, which  are  always  the  most  copious,  fall  while  the  sun  is  in 
the  neighborhood  of  the  zenith.  In  the  northern  hemisphere,  the 
greatest  quantity  of  rain  falls  during  winter ;  and  at  places  some- 
what far  south  on  the  temperate  zone,  the  summer  rain  is  altogether 
insignificant.  In  assuming  the  number  100  to  express  the  whole 
annual  quantity  of  rain,  we  should  have  in 

Madeira..  Lisbon. 

Winter 51  40 

Spring 16  34 

Summer 3  3 

Autumn 30  23 

Less  rain  falls  in  the  eastern  parts  of  Europe  than  in  the  western. 
The  annual  rain,  too,  is  distributed  very  unequally  over  the  diflferent 
seasons,  as  has  been  shown  by  M.  Gasparin  in  a  remarkable  paper. 
If  we  express  by  100  the  quantity  of  rain  gauged  in  a  year,  we 
should  have  for  each  season  : 

In  the  weit  of  West  of  East  of  Germany.  St.  Petersburjf. 

Enrland.  France.  France. 

Winter 26  23              20              18              14 

Spring 20  13               23               22               18 

Summer 23  25              2d              37              37 

Autumn   31  34              28              23              30 

The  quantity  of  rain  which  falls  in  the  course  of  a  year  varies 
considerably  according  to  the  climate  ;  to  form  an  idea  of  the  extent 
of  these  variations,  it  is  enough  to  notice  the  results  obtained  at  dif- 
ferent observatories ;  but  it  is  less  the  annual  quantity  of  rain  that 
falls,  than  the  way  or  quantities  in  which  it  is  distributed  over  the 
diflferent  months  of  the  year,  which  interests  the  farmer ;  upon  this 
distribution,  in  fact,  in  many  districts,  depend  the  productiveness 
and  fertility  of  the  soil.  I  add  a  table  of  the  mean  quantities  of  rain 
in  inches  and  lOths,  that  fall  at  London  in  the  diflferent  months  of 
the  year : 

Jan.        Feb.     March.    April.      May.       June.       July.       Aug.       Sept.        Oct.        Not.        Dec. 
in.  in.  in.  in.  in.  in.  in.  in.  in.  in.  in.  in. 

1.45       1.25       1.17      1.29       1.61       1.72       2.39       1.80       1.84       2.08       2.20       1.72 

^  V.    ON  THK  INFLUENCE  OF  AGRICULTURAL  LABORS  ON  THE  CLIMATE 
OF  A  COUNTRY  IN  LESSENING  STREAMS,  ETC. 

A  question  of  great  importance,  and  that  is  frequently  agitated  a 
this  time,  is,  as  to  whether  the  agricultural  labors  of  man  are  influ- 
ential in  modifying  the  climate  of  a  country  or  not  1  Do  extensive 
clearings  of  woods,  the  draining  and  drying  up  of  great  swamps, 
which  certainly  influence  the  distribution  of  heat  during  the  differ- 
ent seasons  of  the  year,  also  exert  an  influence  on  the  quantity  of 
running  water  of  a  country,  whether  by  lessening  the  quantity  of 
rain  which  falls,  or  by  promoting  the  more  speedy  evaporation  of 
that  which  has  fallen  1 

lit  sojae  districts  it  has  been  held,  that  the  streams  which  ha4 


496  INFLUENCE  OF  AGRICULTURE  ON  CLIMATE. 

Deen  used  as  moving  powers,  have  very  sensibly  diminished.  In 
other  places,  the  rivers  are  said  to  have  shrunk  visibly ;  and  in 
others,  springs  that  were  formerly  abundant,  have  almost  dried  up. 
Observations  to  this  effect  appear  to  have  been  principally  made  in 
valleys,  surmounted  by  mountains  ;  and  it  is  generally  asserted,  that 
the  falling  off  in  the  springs  and  streams,  had  followed  close  upon 
the  period  at  which  the  woods,  scattered  over  the  surface  of  the 
country,  were  cleared  away  without  any  kind  of  reserve. 

These  statements,  which  may  be  assumed  as  facts,  see.o  to  indi- 
cate that  where  the  woods  have  been  felled,  it  rains  less  than  it  did 
formerly ;  this,  indeed,  is  the  general  opinion  entertained  on  the 
subject ;  and  were  it  admitted,  without  further  examination,  the 
natural  inference  from  it  would  be,  that  the  extension  of  agriculture 
diminishes  the  annual  quantity  of  rain  which  falls  in  a  country.  But 
at  the  same  time  that  the  facts  as  stated  have  been  observed,  it  has 
further  been  noticed  that  since  the  clearing  of  the  surface  from  for- 
ests, the  torrents  and  rivers  which  seemed  to  have  lost  in  amount 
of  regular  supply  of  water,  had  become  subject  to  sudden  and  extra- 
ordinary risings  which  had  proved  the  cause  of  numerous  and  grave 
calamities.  In  the  same  way,  springs  that  are  generally  all  but  dry, 
have  been  seen  to  burst  forth  again  abundantly  after  violent  storms. 
These  latter  observations,  as  may  readily  be  imagined,  are  of  a  kind 
that  should  lead  us  not  lightly  to  embrace  the  vulgar  opinion,  which 
maintains  that  the  cutting  down  of  the  woods  has  had  the  effect  of 
lessening  the  mean  annual  quantity  of  rain  :  it  is  not  only  not  impos- 
sible that  this  quantity  has  not  varied,  but  it  may  even  happen  that 
the  mass  of  water  which  passes  over  the  bed  of  a  stream,  supposed 
shrunken,  is  actually  the  same  as  ever  it  was ;  the  only  difference 
may  be,  that  now  the  flow  is  much  less  regular  than  it  used  to  be  : 
in  former  times  the  bed  was  always  and  more  moderately  full ;  at 
present  it  is  excessively  full  at  intervals  only.  It  is  very  possible, 
therefore,  that  here  as  elsewhere,  occasionally,  the  appearance  of 
the  fact  has  been  taken  for  the  reality.  It  were  very  important  to 
discover  some  natural  index  to  a  solution  of  the  question  at  issue  : 
whether  or  not  the  destruction  of  the  forests  that  once  covered  the 
face  of  a  district  of  country,  had  had  the  effect  of  lessening  the  mean 
annual  fall  of  rain  ? 

The  lakes  which  are  met  with  in  plains,  and  at  different  levels  in 
mountain  ranges,  seem  to  me  peculiarly  well  calculated  to  throw 
.ight  on  this  subject.  Lakes  may,  in  fact,  be  received  as  natural 
gauges  of  the  running  waters  of  a  country.  If  the  mass  of  the  water 
contained  in  the  lakes  undergo  change  in  one  direction  or  another,  it 
is  obvious 'that  this  change,  and  the  direction  in  which  it  has  occur- 
red, will  be  proclaimed  by  the  state  or  mean  level  of  the  lake  or 

akes,  which  will  differ  for  the  same  reason  that  it  does  at  different 
seasons  of  the  year,  viz.  as  drought  or  rain  prerails.     The  mean 

evel  of  the  lake  or  lakes  of  a  district  will,  therefore,  fall,  if  the 
quantity  of  water  which  flows  through  that  district  diminishes  ;  the 

evel,  on  the  contrary,  will  rise,  if  its  streams  increase ;  and  it  will 

remain  stationary  if  the  afflux  and  efflux  of  the  lake  continue  ud 


INFLUENCE  OF  AGRICULTURE  ON  CLIMATE.  497 

changed.  In  the  following  remarks,  I  shall  attach  myself  particu- 
larly to  observations  upon  lakes  which  have  no  outlet,  by  reason  of 
the  facility  with  which  any  even  slight  change  in  the  level  of  these 
must  be  discovered.  I  shall  not,  however,  neglect  those  lakes 
which  have  an  exit  by  a  stream  or  canal,  because  I  believe  that  the 
study  of  these  may  also  lead  to  accurate  enough  results  ;  the  only 
point  requiring  preliminary  remark,  is  the  sense  in  which  the  words, 
change  of  level,  are  to  be  taken. 

Geologists  admit,  that  the  level  of  the  waters  upon  the  surface  of 
the  globe  has  everywhere  undergone  great  changes,  whether  atten- 
tion be  directed  to  the  shores  of  the  sea  or  to  those  of  great  inland 
lakes.  This  fact  is  universal,  and  is  questioned  by  none,  but  great 
diversity  of  opinion  prevails  in  regard  to  the  cause  of  the  phenome- 
non. Some  pretend,  that  in  many  cases  the  change  of  level  is  only 
apparent, — that  the  body  of  water  has  not  sunk,  but  that  the  shores 
have  risen  ;  others,  again,  maintain  that  there  has  been  a  true  dimi- 
nution in  the  mass  of  fluid,  a  true  drying  up,  and  that  its  level  has 
actually  sunk.  I  shall  not,  in  this  place,  enter  upon  the  great  geo- 
logical question  ;  the  variations  which  are  there  signalized  are  often 
of  vast  extent,  and  involve  the  supposition  of  violent  catastrophes, 
which,  in  a  general  way,  were  long  anterior  to  the  historical  epoch. 
I  shall  only  refer  to  changes  of  level  observed  in  lakes  by  our  ances- 
tors or  contemporaries ;  in  a  word,  to  facts  which  have  taken  place 
under  the  eyes  of  men,  inasmuch  as  it  is  the  influence  of  their  ag- 
ricultural labors  upon  the  meteorological  state  of  the  atmosphere, 
which  I  am  seeking  to  appreciate.  The  facts  upon  which  I  shall 
more  particularly  dwell,  were  observed  in  South  America  ;  but  I 
shall  show  that  what  is  true  with  regard  to  this  continent,  is  true 
also  with  reference  to  any  other  continent. 

One  of  the  most  interesting  portions  of  Venezuela  is,  undoubtedly, 
the  valley  d'Aragua.  Situated  at  a  short  distance  from  the  sea- 
board, possessed  of  a  warm  climate,  and  of  a  soil  fertile  beyond  ex- 
ample, it  combines  within  itself  all  the  varieties  of  agriculture  that 
belong  in  peculiar  to  tropical  regions  ;  on  the  hillocks  which  rise  in 
the  bottom  of  the  valley,  are  seen  fields  which  bring  to  mind  the 
agriculture  of  Europe.  Wheat  succeeds  pretty  well  upon  the  heights 
which  surround  La  Vittoria.  Bounded  on  the  north  by  a  chain  of 
hills  which  run  parallel  with  the  sea-board,  and  to  the  south  by  the 
range  which  separates  it  from  Llanos,  the  Aragua  Valley  is  limited 
on  the  east  and  west  by  a  series  of  lesser  elevations,  which  shut  it 
in  completely.  In  consequence  of  this  peculiar  configuration  of 
country,  the  rivers  which  rise  in  its  interior  have  no  outlet  to  the 
ocean  ;  their  waters  accumulate  in  the  lowest  part  of  the  valley,  and 
form  the  beautiful  lake  Valentia.  This  lake,  which  M.  de  Humboldt 
says  exceeds  the  lake  Neufch^tel  in  size,  is  raised  about  1300  feet 
above  the  level  of  the  sea ;  it  is  about  ten  leagues  in  length,  and 
about  two  leagues  and  a  half  where  it  is  widest. 

At  the  time  when  M.  de  Humboldt  visited  the  Aragua  Valley,  the 
inhabitants  were  struck  with  the  gradual  diminution  which  had  been 
going  on  in  the  waters  of  the  lake  during  the  last  thirty  years.     J^ 

42* 


498  INFLUENCE  OF  AGRICULTURE  ON  CLIMATE. 

was  enough  to  compare  the  statements  of  older  writers  with  its  con  • 
dition  at  this  time,  to  obtain  conviction  that  the  waters  had,  in  fact, 
rery  much  diminished.  Oviedo,  for  instance,  who  visited  the  valley 
frequently  towards  the  end  of  the  sixteenth  century,  says,  that  the 
town  of  New  Valencia  was  founded  in  1555,  at  the  distance  of  half  a 
league  from  the  lake  ;  in  1800,  M.  de  Humboldt  ascertained  that  the 
lake  was  upwards  of  549  yards,  or  upwards  of  3y  miles,  instead  of 
about  If  mile  from  its  banks. 

The  appearance  of  the  surface  also  gives  new  proof  of  the  fact  of 
the  recession  of  the  water ;  certain  hillocks  which  rise  in  the  plain 
still  preserve  the  title  of  islands,  which,  undoubtedly,  they  formerly 
received  with  propriety,  when  they  were  surrounded  by  water.  The 
land  which  had  been  left  by  the  retreat  of  the  lake,  soon  became 
transformed  into  beautiful  plantations  of  cotton-trees,  bananas,  and 
sugar-canes.  Buildings  which  had  been  erected  on  the  banks  were 
left,  year  after  year,  further  and  further  from  them.  In  1796,  new 
islets  made  their  appearance.  An  important  military  position,  a  for- 
tress built  in  1740,  in  the  Isle  de  la  Cabrera,  was  then  upon  a  penin- 
sula. Finally,  in  two  islets  of  granite,  M.  de  Humboldt  discovered, 
several  yards  above  the  level  of  the  lake,  a  bed  of  fine  sand,  mixed 
with  fresh-water  shells.  These  facts,  so  certain,  so  unquestionable, 
did  not  pass  without  numerous  explanations  from  the  wise  men  of 
the  country,  who,  as  if  by  common  consent,  fixed  upon  a  subterra- 
nean exit  for  the  waters  of  the  lake.  M.  de  Humboldt,  after  the 
most  careful  examination  of  all  the  circumstances,  did  not  hesitate 
to  ascribe  the  diminution  of  the  waters  of  the  lake  Valencia  to  the 
extensive  clearings  which  had  been  effected  in  the  course  of  half  a 
century  in  the  Aragua  valley.  "  In  felling  the  trees  which  covered 
the  crowns  and  slopes  of  the  mountains,"  says  this  celebrated 
traveller,  *'  men  in  all  climates  seem  to  be  bringing  upon  future 
generations  two  calamities  at  once — a  want  of  fuel  and  a  scarcity 
of  water."* 

In  the  year  1800,  the  population  of  this  favored  valley,  where  the 
cultivation  of  indigo,  of  cotton,  of  cocoa,  and  the  cane  had  made  im- 
mense progress,  was  as  dense  as  it  was  in  the  most  thickly  popula- 
ted districts  of  England  or  France,  and  every  one  was  delighted 
with  the  appearance  of  comfort  that  prevailed  in  the  numerous  villa- 
ges of  this  industrious  country. 

Twenty-five  years  after  M.  de  Humboldt,  I  explored  in  my  turn 
the  Valley  d'Aragua,  having  fixed  my  residence  in  the  little  town  of 
Maracaibo.  The  inhabitants  had  now  remarked  that  for  several 
years,  not  only  had  the  lake  ceased  to  diminish,  but  that  it  had  even 
risen  very  perceptibly.  Some  fields  that  were  formerly  covered  with 
cotton  plantations  were  now  submerged.  The  Isles  de  las  Nuevas 
Aparacidas,  which  had  risen  from  the  waters  in  1796,  had  again  be- 
come shoals  dangerous  to  navigation  ;  the  tongue  of  earth,  De  la 
Cacrera,  on  the  north  side  of  the  valley,  had  become  so  narrow  that 
tl)6  gligh  est  rise  in  the  water  of  the  lake  covered  it  completely ;  a 


•  Humboldt,  vol  v.  p.  173. 


I 


INFLUENCE  OF  AGRICULTURE   ON  CLIMATE.  499 

continuous  N.E.  wind  was  sufficient  to  flood  the  road  which  led 
from  Maracaibo  to  New  Valencia ;  in  short,  the  fears  which  the  in- 
habitants of  the  lake  had  entertained  for  so  long  a  period  had  entirely 
changed  their  nature  ;  they  were  now  no  longer  afraid  of  the  lake  dry- 
ing up  ;  they  saw  with  dismay  that  if  the  water  continued  to  rise  as 
it  had  done  lately,  it  would  in  no  long  space  of  time  have  drowned 
some  of  the  most  valuable  estates,  &c.  Those  who  had  explained 
the  diminution  of  the  lake  by  supposing  subterraneous  canals,  now 
hastened  to  close  them  up  in  order  to  find  a  cause  for  the  rise  in  the 
level  of  the  water. 

In  the  course  of  the  last  twenty-two  years  important  political 
events  had  transpired.  Venezuela  no  longer  belonged  to  Spain ;  the 
peaceful  valley  d'Aragua  had  been  the  theatre  of  many  a  bloody  con- 
test ;  war  to  the  knife  had  desolated  this  beautiful  country  and  deci- 
mated its  inhabitants.  On  the  first  cry  of  independence  raised,  a 
great  number  of  slaves  found  freedom  by  enlisting  under  the  banners 
of  the  new  republic  ;  agricultural  operations  of  any  extent  were 
abandoned,  and  the  forest,  which  makes  such  rapid  progress  in  the 
tropics,  had  soon  regained  possession  of  the  surface  which  man  had 
won  from  it  by  something  like  a  century  of  sustained  and  painful 
toil.  With  the  increasing  prosperity  of  the  valley  many  of  the  prin- 
cipal tributaries  to  the  lake  had  been  turned  aside  to  serve  as  means 
of  irrigation,  so  that  the  beds  of  some  of  the  rivers  were  absolutely 
dry  for  more  than  six  months  in  the  year.  At  the  period  which  I 
now  refer  to,  the  water  was  no  longer  used  in  this  way,  and  the  beds 
of  the  rivers  were  full.  Thus  with  the  growth  of  agricultural  indus- 
try in  the  Valley  d'Aragua,  when  the  extent  of  cleared  surface  was 
continually  on  the  increase,  and  when  great  farming  establishments 
were  multiplied,  the  level  of  the  water  sunk ;  but  by  and  by,  during 
a  period  of  disasters,  happily  passing  in  their  nature,  the  process  of 
clearing  is  arrested,  the  lands  formerly  won  from  the  forest  are  in 
part  restored  to  it,  and  then  the  waters  first  cease  to  fall  in  their  le- 
vel, and  by  and  by  show  an  unequivocal  disposition  to  rise. 

I  shall  now,  without,  however,  quitting  America,  carry  my  read- 
ers into  a  district  where  the  climate  is  analogous  to  that  of  Europe, 
where  the  surface  is  occupied  by  immense  fields,  covered  with  the 
cereals  as  with  us.  I  speak  of  the  table-knds  of  New  Granada,  of 
those  valleys  raised  from  10,000  to  13,000  and  14,000  feet  above 
the  level  of  the  sea,  in  which  the  mean  temperature  throughout  the 
year  ranges  from  58°  to  about  62°  Fahr.  Lakes  are  frequent  in  the 
Cordilleras ;  and  it  would  be  easy  for  me  to  describe  a  great  num- 
ber ;  I  shall,  however,  confine  myself  to  those  which  became  subjects 
of  observation  in  former  times. 

The  village  of  Ubate  is  now  situated  in  the  neighborhood  of  two 
lakes.  Some  seventy  years  ago  these  two  lakes  formed  but  one  ; 
the  old  inhabitants  saw  the  water  shrinking  and  new  fields  pre- 
senting themselves  year  after  year.  At  this  present  time  fields  of 
wheat  of  extraordinary  luxuriance  occupy  levels  that  were  com- 
pletely inundated  30  years  ago. 

It  is  enough  indeed  to  perambulate  the  neighborhood  of  Ubate 


500  METEOROLOGY. 

to  consult  the  old  sportsmen  of  the  country,  and  to  refer  to  the 
annals  of  the  various  parishes,  to  be  satisfied  that  extensive  forests 
have  been  cut  down  in  the  whole  of  the  surrounding-  country  :  the 
clearing,  in  fact,  still  continues ;  and  it  is  certain  that  the  recession 
of  the  waters,  although  much  slower  than  it  was  in  former  times,  has 
not  yet  entirely  ceased. 

A  lake,  situated  in  the  same  valley,  to  the  east  of  Ubate,  deserves 
our  particular  attention.  By  means  of  barome  trie  measurements, 
made  with  extreme  care,  I  found  that  this  lake  had  precisely  the 
same  level  as  that  of  Ubate.  Nearly  two  centuries  ago,  it  was  vis- 
ited by  Piedrahita,  Bishop  of  Panama,  an  author  of  great  accuracy, 
to  whom  we  owe  the  history  of  the  conquest  of  New  Granada.  He 
states  this  lake  to  be  ten  leagues  in  length,  by  three  leagues  in 
breadth ;  but  Dr.  Roulin  having  had  occasion,  a  few  years  ago,  to 
make  a  plan  of  the  lake,  he  found  it  a  league  and  a  half  in  length,  by 
one  league  in  breadth ;  my  own  impression  is,  that  at  the  time 
Piedrahita  wrote,  there  was  but  a  single  lake,  extending  all  the  waj 
from  Ubate  to  Zimijaca,  not  two  lakes  as  at  present,  a  supposition 
which  would  take  away  every  thing  like  exaggeration  from  the  state- 
ment of  Piedrahita.  But  the  fact  of  the  retreat  of  the  waters  of 
these  lakes  is  unquestioned ;  the  inhabitants  of  Zimijaca  all  know 
that  the  village  was  founded  close  to  the  lake,  whereas,  at  the  pres- 
ent time,  it  is  nearly  a  league  from  its  banks.  Formerly,  there  was 
no  difficulty  in  obtaining  all  the  building  timber  that  was  wanted  ; 
the  mountains  which  rose  from  the  valley  on  either  hand  were  cov- 
ered up  to  a  certain  height  with  the  trees  proper  to  these  cold  re 
gions ;  the  oak  of  the  Andes  abounded;  numerous  myrcias  were 
also  in  existence,  from  which  abundance  of  wax  was  obtained  :  at 
the  present  time  these  mountains  are  almost  stripped  of  their  trees, 
an  event  mainly  brought  about  by  the  eagerness  to  procure  fuel  in 
manufacturing  salt  from  the  springs  of  Taosa  and  Enemocon. 

To  these  authentic  facts,  which  I  could  multiply  and  support  by 
many  others  of  a  similar  kind,  it  may  be  replied,  that  the  diminution 
of  the  water,  incontestable  as  it  is,  might  perhaps  have  taken  place 
without  the  clearing  away  of  the  forests.  It  may  indeed  be  main- 
tained, that  the  drying  up  of  the  waters  is  owing  to  a  totally  differ- 
ent cause,  altogether  unknown  to  us ;  that  it  must  be  ranked  among 
the  numerous  phenomena,  the  reality  of  which  we  perceive,  but 
without  being  able  to  render  any  account  of  their  cause. 

I  cannot,  in  the  instance  last  quoted,  as  in  that  of  the  lake  of  Va- 
lencia, refer  to  any  increase  of  the  lake  connected  with  the  suspen- 
sion of  agriculture,  or  the  reappearance  of  the  forest.  I  might, 
however,  adduce  in  favor  of  the  opinion  which  I  defend,  the  slow- 
ness with  which  the  decrease  in  the  lakes  of  the  valley  of  Ubate  has 
lately  gone  on,  and  since  the  felling  of  trees  in  the  neighborhood 
nas  almost  entirely  ceased.  Extensive  plots  of  fertile  ground  are 
now  no  longer  left  dry  and  available  to  the  husbandman  by  the  re- 
reat  of  the  lake  ;  he  already  begins  to  think  of  means  for  obtaining 
oy  artifice  that  which  nature,  assisted  by  the  clearing  of  the  country 
presented  him  with  in  former  times.    In  the  year  1826  there  was  » 


METEOROLOGY.  501 

Bpeculation  on  foot  for  draining  the  valley  completely  by  cutting  a 
canal  and  letting  off  the  water.  Further  proof  of  the  fact  which  1 
am  urging  is  obtained  in  another  way.  It  is  not  difficult  to  show, 
that  lakes  in  the  immediate  vicinity  of  those  that  have  shrunk  most 
remarkably,  but  around  which  no  destruction  of  the  forest  has  taken 
place,  have  undergone  no  change  in  their  level.  The  lake  of  Tota, 
situated  at  no  great  distance  from  the  valley  of  Ubate,  at  an  eleva- 
tion that  must  approach  13,000  feet  above  the  level  of  the  sea,  in  a 
region  where  vegetation  has  almost  entirely  disappeared,  has  pre- 
served its  pristine  level  unaltered.  The  lake  is  nearly  circular  ; 
and  Piedrahita,  in  1542,  gives  it  two  leagues  in  breadth.  It  is  sub- 
ject to  violent  storms,  which  render  its  navigation  dangerous  ;  and 
even  travelling  along  its  banks,  from  the  particular  circumstances  in 
which  the  road  is  situated,  with  tho  .ake  on  one  hand  and  a  perpen- 
dicular cliff  upon  the  other,  is  not  without  risk.  In  1652,  the  road 
passed  as  it  does  at  present,  the  water  laving  the  foot  of  the  same 
rocks,  and  its  level  having  suffered  no  change,  any  more  than  the 
sterile  country  which  surrounds  it. 

I  shall  conclude  what  I  have  to  say  on  the  lakes  of  South  America 
by  speaking  of  that  of  Quilatoa,  because  it  has  been  made  the  subject 
of  accurate  observations  sufficiently  remote  from  one  another — 1740 
and  1831. 

Living  at  Latacunga,  a  town  situated  at  no  great  distance  from 
Cotopaxi,  the  traveller  is  sure  to  hear  of  the  wonders  of  the  Laguna 
da  Quilatoa.  From  time  to  time  this  lake,  it  is  said,  casts  forth 
flames  which  set  fire  to  the  shrubs  and  withered  grass  that  grow 
upon  its  banks,  and  frequent  detonations  are  heard,  the  sound  of 
which  extends  to  a  great  distance.  M.  de  la  Condamine,  in  1738, 
visited  this  lake,  which  he  found  of  a  circular  form,  and  about  1278 
feet  in  diameter ;  on  the  28th  November,  1831, 1  also  visited  the 
Lake  of  Quilatoa.  It  cannot  be  better  compared  to  any  thing  than 
to  the  crater  of  a  volcano  filled  with  water ;  I  found  it  nearly  13,000 
feet  above  the  level  of  the  sea,  in  the  cold  region,  therefore  ;  and 
indeed  it  is  surrounded  with  immense  pastures ;  but  the  information 
which  I  obtained  from  the  shepherds  in  the  neighborhood  of  the  Lake 
of  Quilatoa,  dissipated  all  that  was  marvellous  in  its  history  ;  they 
had  never  seen  any  flames  issue  from  its  bosom,  they  had  never 
heard  any  detonations ;  in  short,  I  found  the  lake  as  M.  de  la  Con- 
damine appears  to  have  found  it,  every  thing  having  remained  for 
nearly  a  century  without  change. 

The  study  of  the  lakes  which  are  so  common  in  Asia,  would 
probably  supply  conclusions  similar  to  those  deduced  from  observa- 
tions made  in  South  America,  viz.,  that  the  waters  which  irrigate  a 
country  diminish  as  the  forests  are  cleared  away,  and  as  agriculture 
extends.  The  recent  labors  of  M.  de  Humboldt,  which  have  thrown 
so  much  new  light  upon  this  quarter  of  the  world,  appear  to  leave 
no  doubt  upon  the  subject.  After  having  shown  that  the  system  of 
the  Altai  is  about  to  lose  itself  by  a  succession  of  slopes  in  the 
steppes  of  Kirgiz,  and  that  consequently  the  Ural  chain  is  not  con- 
nected with  that  of  the  Altai,  as  was  generally  belioved,  this  celebrated 


ft02  METEOROLOGY. 

geographer  shows,  that  precisely  in  the  situation  where  the  Alghinic 
mountains  are  usually  set  down,  a  remarkable  region  of  lakes  com- 
mences, which  extend  into  the  plains  that  are  traversed  by  the  Ichim 
the  Omsk,  and  the  Obi.*  It  would  appear  that  these  numerous 
lakes  are  remainders  as  it  were  of  an  immense  sheet  of  water,  which 
formerly  covered  the  whole  of  the  country,  and  which  had  become 
divided  into  so  many  particular  lakes  by  the  configuration  of  the 
surface.  In  crossing  the  steppe  of  Baraba,  in  his  way  from  Tobolsk 
to  Baraoul,  M.  de  Humboldt  perceived  everywhere  that  the  drying 
up  of  waters  increases  rapidly  under  the  influence  of  tile  cultivation 
of  the  soil. 

Europe  also  possesses  its  lakes ;  and  we  have  still  to  examine 
them  from  the  particular  point  of  view  which  engages  us.  M.  de 
Saussure,  in  his  first  inquiries  in  regard  to  the  temperature  of  the 
lakes  of  Switzerland,  examined  those  which  are  situated  at  the  foot 
of  the  first  line  of  the  Jura.  The  Lake  of  NeufchS.tel  is  eight 
leagues  in  length,  and  its  greatest  breadth  does  not  exceed  two 
leagues.  On  visiting  it,  Saussure  was  struck  with  the  extent  which 
this  lake  must  formerly  have  possessed  ;  for,  as  he  says,  the  ex- 
tensive level  and  marshy  meadows  which  terminate  it  on  the  south- 
west, had  unquestionably  been  covered  with  water  at  a  former 
period. 

The  Lake  of  Bienne  is  three  leagues  long  and  one  broad  ;  it  is 
separated  from  the  Lake  of  Neufch^tel  by  a  succession  of  plains  that 
were  probably  inundated. 

Lake  Morat  is  also  separated  from  the  Lake  of  Neufch4tel  by  low 
and  level  marshes,  which  beyond  all  question  were  formerly  sub- 
merged. Unquestionably,  adds  Saussure,  the  three  great  lakes  of 
Neufch^tel,  Bienne,  and  Morat,  were  formerly  connected,  and  formed 
one  great  sheet  of  water.f 

In  Switzerland,  as  in  America  and  Asia,  the  old  lakes,  those  thai 
may  be  spoken  of  under  the  title  of  the  primitive  lakes,  and  which 
occupied  the  bottoms  of  the  valleys  when  the  country  was  unculti- 
vated and  wild,  have  become  divided,  and  now  form  a  variable  num- 
ber of  smaller  and  independent  lakes.  I  shall  wind  up  the  present 
subject  by  referring  to  the  observations  of  Saussure  upon  the  Lake 
of  Geneva,  which  may  be  looked  upon  as  the  starting  point  of  the 
admirable  works  of  this  distinguished  philosopher. 

Saussure  admits,  that  at  an  epoch  long  anterior  to  the  times  of 
history,  the  mountains  which  surround  this  lake  were  themselves 
submerged ;  a  great  catastrophe  let  off  this  immense  collection  of 
water,  and  by  and  by  the  current  possessed  no  more  than  the  bottom 
of  the  valley  ;  the  Lake  of  Geneva  was  formed. 

In  merely  considering  the  monuments  left  by  man,  it  is  impossible 
to  doubt  that  within  1200  or  1300  years  the  waters  of  the  Lake  of 
Geneva  have  gradually  fallen  in  their  level.  It  is  evidently  upon 
the  levels  which  have  thus  been  left  that  the  quarter  de  Rive,  and 
the  lower  streets  of  the  city  of  Geneva  have  been  built.     This  de 

♦  Humboldt,  Fragmens  Asiatiques,  t.  i.  p.  40-50. 
t  Saussure,  Voyage  dans  les  Alpes,  t.  ii.  chap.  6. 


METEOBOLOGY.  508 

pression  of  the  surface,  continues  Saussure,  is  not  merely  the  effect 
of  any  deepening  of  the  bed  of  the  Rhone,  by  which  the  lake  is  dis- 
charged ;  it  has  also  been  produced  by  a  diminution  in  the  quantity 
of  water  which  flows  into  it. 

The  conclusions  which  it  seems  legitimate  to  draw  from  the  ob- 
servations of  Saussure  are,  that  in  the  course  of  from  1200  to  1300 
years  the  quantity  of  running  water  has  sensibly  diminished  in  the 
districts  around  the  Lake  of  Geneva.  No  one  will,  I  apprehend, 
deny  that  in  this  long  period  there  have  not  been  extensive  clear- 
ings of  forest  lands  in  Switzerland,  and  a  continual  increase  in  the 
extent  of  cultivated  land  in  this  beautiful  country.  Here,  conse- 
quently, as  elsewhere,  an  attentive  examination  of  "the  levels  of  the 
lakes  leads  us  to  conclude,  that  where  extensive  clearings  froja  for- 
est have  been  effected,  where  agriculture  has  extended,  that  there 
has  in  all  probability  been  diminution  of  the  running  waters  which 
irrigate  the  surface ;  while  in  those  districts  where  no  change  has 
been  effected,  the  amount  of  running  stream  does  not  appear  to  have 
undergone  any  variation. 

The  effect  of  forests  considered  in  this  point  of  view  would  there- 
fore be  to  keep  up  the  amount  of  the  waters  which  are  destined  for 
mills  and  canals ;  and  next  to  prevent  the  rain-water  from  collecting 
and  flowing  away  with  too  great  rapidity.  That  a  soil  covered  with 
trees  is  further  less  favorable  to  evaporation  than  ground  that  has 
been  cleared,  is  a  truth  that  all  will  probably  admit  without  discus- 
sion. To  be  aware  that  it  is  so,  it  is  enough  to  have  travelled,  a 
short  time  after  the  rainy  season,  upon  a  road  which  traverses  in 
succession  a  country  that  is  free  from  forests,  and  one  that  is  thickly 
wooded.  Those  parts  of  the  road  that  pass  through  the  unencum- 
bered country  are  found  hard  and  dry,  while  those  that  traverse  the 
wooded  districts  are  wet,  muddy,  and  often  scarcely  passable.  In 
South  America,  more  perhaps  than  anywhere  else,  does  the  obsta- 
cle to  evaporation  from  a  soil  thickly  shaded  with  forests,  strike  the 
traveller.  In  the  forests  the  humidity  is  constant,  it  exists  long  after 
the  rainy  season  has  passed ;  and  the  roads  that  are  opened  through 
them  remain  through  the  whole  year  deeply  covered  with  mire  :  the 
only  means  known  of  keeping  forest  ways  dry,  is  to  give  them  a 
width  of  from  260  to  330  feet,  that  is  to  say,  to  clear  the  country  in 
their  course. 

If  once  the  fact  is  admitted  that  running  streams  are  diminished 
in  size  by  the  effect  of  felling  the  forests  and  the  extension  of  agri- 
culture, it  imports  us  to  examine  whether  this  diminution  proceeds 
from  a  less  quantity  of  rain,  or  from  a  greater  amount  of  evapora- 
tion, or  whether  perchance  it  maybe  owing  to  the  practice  of  irrigation. 

I  set  out  with  the  principle  that  it  must  be  next  to  impossible  to 
specify  the  precise  share  which  each  of  these  diflferent  causes  has 
in  the  general  result;  I  shall,  nevertheless,  endeavor  to  appreciate 
them  in  a  summary  way.  The  discussion  will  have  gained  some- 
thing if  it  be  proved  that  there  may  be  diminution  of  running  streams 
'n  consequence  of  clearing  off  the  forests  alone,  without  the  whole 
of  the  causes  being  presumed  to  act  simultaneously. 


504  METEOROLOGy. 

"With  regard  to  irrigation,  it  is  necessary  to  distinguish  between 
that  case  in  which  an  extensive  farm  has  been  substituted  for  an  im- 
penetrable forest,  and  that  in  which  an  arid  soil,  which  never  sup- 
ported wood,  has  been  rendered  productive  by  the  industry  of  man 
In  the  first  case  it  is  very  probable  that  irrigation  will  have  contri- 
buted but  little  to  the  diminution  in  the  mass  of  running  water ;  it 
may  readily  be  imagined  that  the  quantity  of  water  used  up  by  a 
dense  forest  will  equal,  at  all  events,  if  not  exceed,  that  which  wil 
be  required  by  any  of  the  vegetables  which  human  industry  substi- 
tutes for  it.  In  the  second  case,  that  is  to  say,  where  a  great  extent 
of  waste  country  has  been  brought  under  cultivation,  there  will  evi- 
dently be  consumption  of  water  by  the  vegetation  which  has  been 
fostered  upon  the  surface ;  agricultural  industry  will  thus  tend  to 
diminish  the  quantity  of  water  which  irrigates  a  country.  It  is  ex- 
tremely probable  that  it  is  to  a  circumstance  of  this  kind  that  we 
must  ascribe  the  diminution  of  the  lakes  which  receive  so  large  a 
proportion  of  the  running  streams  of  the  north  of  Asia.  It  is  al- 
most unnecessary  to  add,  that  in  circumstances  of  this  kind  the  effect 
which  is  due  to  the  simple  evaporation  of  rain- water  is  not  increased  ; 
the  loss  by  this  means  must  be  rather  less,  because  from  a  surface 
covered  with  plants  evaporation  takes  place  more  slowly  than  from 
one  that  is  devoid  of  vegetation. 

In  the  considerations  which  I  have  presented  upon  the  lakes  of 
Venezuela,  of  New  Granada,  and  of  Switzerland,  the  diminution  may- 
be directly  ascribed  to  a  less  mean  annual  quantity  of  rain ;  but  it 
may  with  equal  reason  be  maintained  to  be  a  simple  consequence  of 
more  rapid  evaporation. 

There  are,  in  fact,  a  variety  of  circumstances  under  the  influence 
of  which  the  diminution  of  running  streams  can  be  shown  to  be  con- 
nected with  more  active  evaporation.  I  shall  confine  myself  to  the 
mention  of  two  particular  instances,  one  noticed  by  M.  Desbassyns 
de  Richemond,  in  the  Island  of  Ascension  ;  the  other  is  from  obser- 
vations by  myself,  and  is  among  the  number  of  facts  which  I  regis 
tered  during  my  residence  for  several  years  at  the  mines"  of  Mar 
mato. 

In  the  Island  of  Ascension  there  was  an  excellent  spring  situated 
at  the  foot  of  a  mountain  originally  covered  with  wood ;  this  spring 
became  scanty  and  dried  up  after  the  trees  which  covered  the  moun- 
tain had  been  felled.  The  loss  of  the  spring  was  rightly  ascribed  to 
the  cutting  down  of  the  timber.  The  mountain  was  therefore  plant- 
ed anew,  and  a  few  years  afterwards  the  spring  reappeared  by  de- 
grees, and  by  and  by  flowed  with  its  former  abundance. 

The  metalliferous  mountain  of  Marmato  is  situated  in  the  province 
of  Popayan,  in  the  midst  of  immense  forests.  The  stream  along 
which  the  mining  works  are  established  is  formed  by  the  junction  of 
several  small  rivulets  which  take  their  rise  in  the  table-land  of  San 
Jorge.  The  country  which  overlooks  the  establishment  is  thickly 
wooded. 

In  1826,  when  I  visited  the  mines  for  the  first  time,  Marmato  con- 
sisted of  a  few  miserable  cabins,  inhabited  by  negro  slaves.     !■ 


METEOROLOGY.  505 

1830,  when  I  quitted  the  country,  Marmato  had  the  most  flourishing 
appearance  •  it  was  covered  with  workshops,  it  had  a  foundry  of 
gold,  machinery  for  grinding  and  amalgamating  the  ores,  &c.,  and  a 
free  population  of  nearly  three  thousand  inhabitants.  It  may  be 
readily  imagined,  that  in  the  course  of  these  four  years  an  immense 
quantity  of  timber  had  been  cut  down,  not  only  for  the  construction 
of  machinery  and  of  houses,  but  as  fuel,  and  for  the  manufacture  of 
charcoal.  For  facility  of  transport,  the  felling  had  principally  gone 
on  upon  the  table-land  of  San  Jorge.  But  the  clearing  had  scarcely 
been  effected  two  years  before  it  was  perceived  that  the  quantity  of 
water  for  the  supply  of  the  machinery  had  notably  diminished.  The 
volume  of  water  had  been  measured  by  the  work  done  by  the  ma- 
chinery, and  actual  gauging  at  diiferent  times  showed  the  progressive 
diminution  of  the  water.  The  question  assumed  a  serious  aspect, 
because  at  Marmato  any  diminution  in  the  quantity  of  the  water, 
which  is  the  moving  power,  would  be  of  course  attended  with  a  pro- 
portional diminution  in  the  quantity  of  gold  produced.  Now,  in  the 
Island  of  Ascension,  and  at  Marmato,  it  is  highly  improbable  that 
any  merely  local  and  limited  clearing  away  of  the  forest  should  have 
had  such  an  influence  upon  the  constitution  of  the  atmosphere  as  to 
cause  a  variation  in  the  mean  annual  quantity  of  rain  which  falls  in 
the  country.  More  than  this,  as  soon  as  the  diminution  of  the 
stream  at  Marmato  was  ascertained,  a  pluviometer,  or  rain-gauge, 
was  set  up,  and  in  the  course  of  the  second  year  of  observation  a 
larger  quantity  of  rain  was  gauged  than  in  the  first  year,  although 
the  clearing  had  been  continued ;  still  there  was  no  appreciable  in- 
crease in  the  size  of  the  running  stream. 

A  couple  of  years  of  observation  are  unquestionably  insufficient  to 
show  any  definitive  variation  in  the  annual  quantity  of  rain  that  falls. 
But  the  observations  made  at  Marmato  still  establish  the  fact  thai 
.he  mass  of  running  water  had  diminished  in  spite  of  the  larger  quanti- 
'y  of  rain  which  fell.  It  is  therefore  probable  that  local  clearings  of 
•brest  land,  even  of  very  moderate  extent,  cause  springs  and  rivu- 
fets  to  shrink,  and  even  to  disappear,  without  the  effect  being  ascri- 
bable  to  any  diminution  in  the  amount  of  rain  that  falls. 

We  have  still  to  inquire,  whether  extensive  clearings  of  the 
forest — clearings  which  embrace  a  whole  country — cause  any  dimi- 
nution in  the  quantity  of  rain  that  falls.  Unfortunately,  the  observa- 
ions  which  we  have  upon  the  quantity  of  rain  which  falls  in  par- 
ticular districts,  are  only  of  sufficient  antiquity  and  accuracy  in 
Europe  to  be  worthy  of  any  confidence,  and  there  the  soil  was  cleared 
before  observation,  in  the  generality  of  instances,  began. 

The  United  States  of  America,  where  the  forests  are  disappearing 
with  such  rapidity,  will  probably  one  day  afford  elements  for  the 
complete  and  satisfactory  solution  of  the  question,  whether  or  not 
the  cutting  down  of  forests  causes  any  diminution  in  the  quantity  of 
rain  which  falls  in  the  course  of  the  year. 

In  studying  the  phenomena  accompanying  the  fall  of  rain  in  the 
tropics,  I  have  come  to  a  conclusion  which  I  have  already  made 
known  to  many  observers.     My  own  opinion  is,  that  the  felling  of 

43 


506  METEOROLOGY 

forests  over  a  large  extent  of  country  has  always  the  effect  of  less 
ening  the  mean  annual  quantity  of  rain.  • 

It  has  long  been  said,  that  in  equinoctial  countries  the  rainy  sea- 
son returns  each  year  with  astonishing  regularity.  There  can  be 
no  doubt  of  the  general  accuracy  of  this  observation,  but  the  mete- 
orological fact  must  not  be  announced  as  universal  and  admitting  of 
no  exception  ;  the  regular  alternation  of  the  dry  and  rainy  season  is 
as  perfect  as  possible  in  countries  which  present  an  extreme  variety 
of  territory.  Thus,  in  a  country  whose  surface  is  covered  with  forests 
and  rivers  and  lakes,  with  mountains  and  plains,  and  table-lands,  the 
periodical  seasons  are  quite  distinct.  But  it  is  by  no  means  so  where 
the  surface  is  more  uniform  in  its  character.  The  return  of  the 
rainy  season  will  be  much  less  regular  if  the  soil  be  in  general  dry 
and  naked ;  or  if  extensive  agricultural  operations  take  the  place  of 
the  primeval  forest ;  if  rivers  are  less  common,  and  lakes  less  fre- 
quent. The  rains  will  then  be  less  abundant ;  and  such  countries 
will  be  exposed,  from  time  to  time,  to  droughts  of  long  continuance 
If,  on  the  contrary,  thick  forests  cover  almost  the  whole  of  the  terri- 
tory, if  its  rivulets  and  rivers  be  numerous,  and  agriculture  be  limited 
in  extent,  irregularity  in  the  seasons  will  then  take  place,  but  in  a 
different  way  ;  the  rains  will  prevail,  and  in  some  seasons  they  will 
become  as  it  were  incessant. 

The  continent  of  America  presents  us,  on  the  largest  scale,  with 
two  regions  placed  in  the  same  conditions  as  to  temperature,  but  in 
which  we  successively  encounter  the  circumstances  which  are  most 
favorable  to  the  formation  and  fall  of  rain  in  one  case,  and  to  its 
absence  in  the  other. 

Setting  out  from  Panama,  and  proceeding  towards  the  south,  we 
encounter  the  Bay  of  Cupica,  the  provinces  of  San  Bonaventura 
Choco,  and  Esmeraldas ;  in  this  country,  covered  with  thick  forests 
and  intersected  with  a  multitude  of  streams,  the  rains  are  almost 
incessant ;  in  the  interior  of  Choco,  scarcely  a  day  passes  without 
rain.  Beyond  Tumbez,  towards  Payta,  an  order  of  things  entirely 
different  commences  :  the  forests  have  entirely  disappeared,  the  soil 
is  sandy,  agriculture  scarcely  exists,  and  here  rain  is  almost  un- 
known. When  I  was  at  Pajrta,  the  inhabitants  informed  me  that  it 
had  not  rained  for  seventeen  years !  The  same  want  of  rain  is 
common  in  the  whole  of  the  country  which  surrounds  the  desert  of 
Sechura,  and  extends  to  Lima ;  in  these  countries  rain  is  as  rare  as 
trees  are. 

In  Choco,  where  the  soil  is  thickly  covered  with  trees,  it  rains 
almost  continually ;  and  on  the  coasts  of  Peru,  where  the  soil  is 
sandy,  without  trees,  and  devoid  of  verdure,  it  never  rains ;  and 
this,  as  I  have  said,  under  a  climate  which  enjoys  the  same  tempera- 
ture, and  whose  general  features  and  distance  from  the  mountains 
are  nearly  the  same.  Piura  is  not  more  remote  from  the  Andes  of 
Assuay  than  are  the  moist  plains  of  Choco  from  the  Western  Cor- 
dillera. 

The  facts  which  ha>e  now  been  laid  before  the  reader  seem  to 
authorize  me  to  infer — 


METEOROLOGY.  507 

Ist.  That  extensive  destruction  of  forests  lessens  the  quantity  of 
running  water  in  a  country. 

2d  That  it  is  impossible  to  say  precisely  whether  this  diminution 
is  due  to  a  less  mean  annual  quantity  of  rain,  or  to  more  active 
evaporation,  or  to  these  two  effects  combined. 

3d.  That  the  quantity  of  running  water  does  not  appear  to  have 
suffered  any  diminution  or  change  in  countries  which  have  known 
nothing  of  agricultural  improvement. 

4th.  That  independently  of  preserving  running  streams,  by  oppo- 
sing an  obstacle  to  evaporation,  forests  economize  and  regulate  their 
flow. 

5th.  That  agriculture  established  in  a  dry  country,  not  covered 
with  forests,  dissipates  an  additional  portion  of  its  running  water. 

6th.  That  clearings  of  forest  land  of  limited  extent  may  cause 
the  disappearance  of  particular  springs,  without  our  being  therefore 
authorized  to  conclude  that  the  mean  annual  quantity  of  rain  has 
been  diminished. 

7th,  and  lastly.  That  in  assuming  the  meteorological  data  collect- 
ed in  intertropical  countries,  it  may  be  presumed  that  clearing  off 
the  forests  does  actually  diminish  the  mean  annual  quantity  of  rain 
which  falls.* 

♦  These  meteorological  observations  are  highly  interesting,  and  worthy  of  every 
consideration.  That  unforesting  a  country  makes  it  absolutely  drier,  seems  unques- 
tionable ;  but  whether  that  be  in  consequence  of  less  rain  falling,  or  of  that  which 
falls  going  further,  making  more  show,  cannot  be  easily  determined.  It  does  not  seem 
very  legitimate  to  decide,  that  because  a  country  is  covered  with  wood,  therefore  it  is 
wet :  the  converse  of  that  proposition  appears  much  more  probable— viz.,  that  because 
a  country  is  wet,  therefore  it  is  covered  with  trees.  There  is  one  part  of  the  ocean 
which  is  called  by  mariners  "  The  Rains  ;"  because  it  rains  there  almoat  ceaselessly, 
as  it  does  in  the  province  of  Choco :  but  "  The  Rains"  has  no  forests  to  account  for 
its  dripping  sky.  Did  that  region  consist  of  dry  land  instead  of  salt-water,  then  doubt- 
less its  surface  would  be  covered,  as  that  of  Choco  is,  with  an  impenetrable  forest 
The  subject  is  adverted  to  here,  however,  not  to  discuss  the  general  question,  but  to 
throw  out  the  suggestion  that  under  the  hand  of  man,  the  soil  and  even  the  climate  of 
our  immense  Australian  possessions  might  possibly  be  improved.  Drought  is  the 
grand  enemy  of  Australian  settlers  ;  and  the  country  is  generally  barren  of  wood. 

Governors,  district  governments,  and  farmers,  and  all  who  are  interested  in  the  pros- 
perity of  the  colony,  surely  ought  to  encourage,  by  every  possible  means,  the  growth 
of  the  taller  trees  and  shrubs  that  are  indigenous  to  the  country. 

Expeditions  might  be  made  once  or  twice  a  year,  at  the  proper  season,  for  scattenn^ 
or  planting  the  seeds  of  these  trees  or  shrubs.  Could  every  knoll  within  a  hundred 
miles  of  Sidney  be  seen  crowned  with  a  thick  screen  of  leafy  trees,  there  can  be  little 
doubt  but  that  the  rain  which  falls  would  be  economized ;  and  that  the  beds  of  the 
rivers,  instead  of  being  dry  for  eight  or  nine  months,  would  be  occupied  all  the  yetti 
round  by  at  least  a  moderate  stream  of  water.— Eno.  Ed. 


THK  END. 


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